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1960473
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1960473/get-all-unique-values-in-a-javascript-array-remove-duplicates
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,960,473
Get all unique values in a JavaScript array (remove duplicates)
2,926
3,759,314
94
true
true
[ "javascript", "unique", "arrays" ]
2009-12-25T04:28:23
2025-08-05T16:57:20
Mottie
true
null
14,438,954
145,346
86,809
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I have an array of numbers that I need to make sure are unique. I found the code snippet below on the Internet, and it works great until the array has a zero in it. I found this other script here on Stack Overflow that looks almost exactly like it, but it doesn't fail. How can I determine where the prototype script is ...
<p>I have an array of numbers that I need to make sure are unique. I found the code snippet below on the Internet, and it works great until the array has a zero in it. I found <a href="https://stackoverflow.com/questions/1890203">this other script</a> here on Stack Overflow that looks almost exactly like it, but it doe...
[ { "answerId": 14438954, "score": 4734, "isAccepted": true, "createdAt": "2013-01-21T12:46:24", "ownerDisplayName": "TLindig", "ownerUserId": 496587, "bodyText": "With JavaScript 1.6 / ECMAScript 5 you can use the native filter method of an Array in the following way to get an array with ...
1
1349404
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1349404/generate-a-string-of-random-characters
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,349,404
Generate a string of random characters
2,915
3,161,342
94
true
true
[ "javascript", "string", "random" ]
2009-08-28T21:14:41
2025-10-28T16:37:44
Tom Lehman
false
CC BY-SA 4.0
1,349,426
25,068
89,939
null
null
null
null
null
null
null
null
null
null
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null
null
null
null
I want a string of fixed length, composed of characters picked randomly from a set of characters e.g. [a-zA-Z0-9] . How can I do this with JavaScript?
<p>I want a string of fixed length, composed of characters picked randomly from a set of characters e.g. <code>[a-zA-Z0-9]</code>.</p> <p>How can I do this with JavaScript?</p>
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2
351409
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/351409/how-to-append-something-to-an-array
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
351,409
How to append something to an array?
2,889
5,522,445
30
true
true
[ "javascript", "arrays", "append" ]
2008-12-09T00:20:05
2024-09-25T10:42:20
interstar
false
CC BY-SA 3.0
351,421
8,482
27,616
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
How do I append an object (such as a string or number) to an array in JavaScript?
<p>How do I append an object (such as a string or number) to an array in JavaScript? </p>
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1
4059147
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/4059147/check-if-a-variable-is-a-string-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
4,059,147
Check if a variable is a string in JavaScript
2,883
3,097,422
35
true
true
[ "javascript", "string" ]
2010-10-30T14:36:34
2025-12-09T14:31:20
Olical
false
CC BY-SA 4.0
4,059,166
455,137
41,752
null
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null
null
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null
null
How can I determine whether a variable is a string or something else in JavaScript?
<p>How can I determine whether a variable is a string or something else in JavaScript?</p>
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2
492994
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/492994/compare-two-dates-with-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
492,994
Compare two dates with JavaScript
2,865
3,600,399
48
true
true
[ "javascript", "date", "datetime", "compare" ]
2009-01-29T19:14:06
2024-03-08T11:22:50
Alex
false
CC BY-SA 4.0
493,018
41,508
40,695
null
null
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null
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null
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null
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null
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Can someone suggest a way to compare the values of two dates greater than, less than, and not in the past using JavaScript? The values will be coming from text boxes.
<p>Can someone suggest a way to compare the values of <strong>two dates</strong> greater than, less than, and not in the past using JavaScript? The values will be coming from text boxes.</p>
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1
2901102
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/2901102/how-can-i-format-a-number-with-commas-as-thousands-separators
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
2,901,102
How can I format a number with commas as thousands separators?
2,781
2,340,658
53
true
true
[ "javascript", "formatting", "numbers" ]
2010-05-24T23:42:31
2026-02-21T12:00:43
Elias Zamaria
false
CC BY-SA 4.0
2,901,298
28,324
101,964
null
null
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I am trying to print an integer in JavaScript with commas as thousands separators. For example, I want to show the number 1234567 as "1,234,567". How would I go about doing this? Here is how I am doing it: function numberWithCommas(x) { x = x.toString(); var pattern = /(-?\d+)(\d{3})/; while (pattern.test(x)) x = x.rep...
<p>I am trying to print an integer in JavaScript with commas as thousands separators. For example, I want to show the number 1234567 as &quot;1,234,567&quot;. How would I go about doing this?</p> <p>Here is how I am doing it:</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="f...
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2
5404839
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/5404839/how-do-i-refresh-a-page-using-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
5,404,839
How do I refresh a page using JavaScript?
2,764
3,226,822
20
true
true
[ "javascript", "jquery", "refresh", "reload" ]
2011-03-23T11:55:31
2026-04-28T08:57:51
luca
false
CC BY-SA 4.0
5,404,869
505,762
37,252
null
null
null
null
null
null
null
null
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null
null
null
null
null
null
How do I refresh a page using JavaScript?
<p>How do I refresh a page using JavaScript?</p>
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1
6677035
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/6677035/scroll-to-an-element-with-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
6,677,035
Scroll to an element with jQuery
2,732
3,248,505
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true
true
[ "javascript", "jquery", "scroll" ]
2011-07-13T09:49:44
2023-08-15T10:19:38
DiegoP.
false
CC BY-SA 4.0
6,677,069
735,997
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null
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I have this input element: <input type="text" class="textfield" value="" id="subject" name="subject"> Then I have some other elements, like other tag's & <textarea> tag's, etc... When the user clicks on the <input id="#subject"> , the page should scroll to the page's last element, and it should do so with a nice animat...
<p>I have this <code>input</code> element:</p> <pre><code> &lt;input type=&quot;text&quot; class=&quot;textfield&quot; value=&quot;&quot; id=&quot;subject&quot; name=&quot;subject&quot;&gt; </code></pre> <p>Then I have some other elements, like other tag's &amp; <code>&lt;textarea&gt;</code> tag's, etc...</p> <p>When...
[ { "answerId": 6677069, "score": 4557, "isAccepted": true, "createdAt": "2011-07-13T09:52:36", "ownerDisplayName": "Steve", "ownerUserId": 343088, "bodyText": "Assuming you have a button with the id button , try this example: $(\"#button\").click(function() { $([document.documentElement, ...
1
2647867
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/2647867/how-can-i-determine-if-a-variable-is-undefined-or-null
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
2,647,867
How can I determine if a variable is 'undefined' or 'null'?
2,718
3,555,136
33
true
true
[ "javascript", "jquery", "variables", "null", "undefined" ]
2010-04-15T18:12:16
2023-12-04T17:15:49
sadmicrowave
false
CC BY-SA 4.0
2,647,888
281,488
41,090
null
null
null
null
null
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How do I determine if a variable is undefined or null ? My code is as follows: var EmpName = $("div#esd-names div#name").attr('class'); if(EmpName == 'undefined'){ // DO SOMETHING }; <div id="esd-names"> <div id="name"></div> </div> But when I do this, the JavaScript interpreter halts execution.
<p>How do I determine if a variable is <code>undefined</code> or <code>null</code>?</p> <p>My code is as follows:</p> <pre class="lang-js prettyprint-override"><code>var EmpName = $(&quot;div#esd-names div#name&quot;).attr('class'); if(EmpName == 'undefined'){ // DO SOMETHING }; </code></pre> <pre class="lang-html pr...
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1
48270127
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/48270127/can-a-1-a-2-a-3-ever-evaluate-to-true
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
48,270,127
Can (a== 1 && a ==2 && a==3) ever evaluate to true?
2,703
435,234
28
true
true
[ "javascript", "ecmascript-6" ]
2018-01-15T20:20:47
2026-01-27T22:01:28
Dimpu Aravind Buddha
false
CC BY-SA 4.0
48,270,314
1,165,332
9,895
null
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Moderator note: Please resist the urge to edit the code or remove this notice. The pattern of whitespace may be part of the question and therefore should not be tampered with unnecessarily. If you are in the "whitespace is insignificant" camp, you should be able to accept the code as is. How is it ever possible that (a...
<blockquote> <p><strong>Moderator note:</strong> Please resist the urge to edit the code or remove this notice. The pattern of whitespace may be part of the question and therefore should not be tampered with unnecessarily. If you are in the &quot;whitespace is insignificant&quot; camp, you should be able to accept the ...
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1
901115
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/901115/how-can-i-get-query-string-values-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
901,115
How can I get query string values in JavaScript?
2,693
5,522,046
73
true
true
[ "javascript", "url", "plugins", "query-string" ]
2009-05-23T08:10:48
2023-06-06T10:08:34
Subliminal Hash
false
CC BY-SA 3.0
901,144
49,742
13,762
null
null
null
null
null
null
null
null
null
null
null
null
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null
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Is there a plugin-less way of retrieving query string values via jQuery (or without)? If so, how? If not, is there a plugin which can do so?
<p>Is there a plugin-less way of retrieving <a href="http://en.wikipedia.org/wiki/Query_string" rel="nofollow noreferrer">query string</a> values via jQuery (or without)? </p> <p>If so, how? If not, is there a plugin which can do so?</p>
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1
894860
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/894860/set-a-default-parameter-value-for-a-javascript-function
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
894,860
Set a default parameter value for a JavaScript function
2,691
1,500,039
30
true
true
[ "javascript", "function", "parameters", "arguments", "default-parameters" ]
2009-05-21T20:07:17
2025-08-14T03:36:04
Tilendor
false
CC BY-SA 4.0
894,877
1,470
49,013
null
null
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null
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I would like a JavaScript function to have optional arguments which I set a default on, which get used if the value isn't defined (and ignored if the value is passed). In Ruby you can do it like this: def read_file(file, delete_after = false) # code end Does this work in JavaScript? function read_file(file, delete_afte...
<p>I would like a JavaScript function to have optional arguments which I set a default on, which get used if the value isn't defined (and ignored if the value is passed). In Ruby you can do it like this:</p> <pre><code>def read_file(file, delete_after = false) # code end </code></pre> <p>Does this work in JavaScrip...
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1
171027
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/171027/adding-a-table-row-in-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
171,027
Adding a table row in jQuery
2,677
2,059,439
42
true
true
[ "javascript", "jquery", "html-table" ]
2008-10-04T21:33:10
2022-08-16T15:48:14
Darryl Hein
false
CC BY-SA 4.0
171,049
5,441
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null
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I'm using jQuery to add an additional row to a table as the last row. I have done it this way: $('#myTable').append('<tr><td>my data</td><td>more data</td></tr>'); Are there limitations to what you can add to a table like this (such as inputs, selects, number of rows)? Is there a different way to do it?
<p>I'm using jQuery to add an additional row to a table as the last row.</p> <p>I have done it this way:</p> <pre><code>$('#myTable').append('&lt;tr&gt;&lt;td&gt;my data&lt;/td&gt;&lt;td&gt;more data&lt;/td&gt;&lt;/tr&gt;'); </code></pre> <p>Are there limitations to what you can add to a table like this (such as inputs...
null
0
952924
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/952924/how-do-i-chop-slice-trim-off-last-character-in-string-using-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
952,924
How do I chop/slice/trim off last character in string using Javascript?
2,624
2,662,110
26
true
true
[ "javascript", "slice", "trim" ]
2009-06-04T20:31:53
2025-02-01T21:44:53
Phill Pafford
false
CC BY-SA 4.0
952,945
93,966
85,658
null
null
null
null
null
null
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null
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null
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null
I have a string, 12345.00 , and I would like it to return 12345.0 . I have looked at trim , but it looks like it is only trimming whitespace and slice which I don't see how this would work. Any suggestions?
<p>I have a string, <code>12345.00</code>, and I would like it to return <code>12345.0</code>.</p> <p>I have looked at <code>trim</code>, but it looks like it is only trimming whitespace and <code>slice</code> which I don't see how this would work. Any suggestions?</p>
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1
4959975
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/4959975/generate-random-number-between-two-numbers-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
4,959,975
Generate random number between two numbers in JavaScript
2,617
2,730,328
34
true
true
[ "javascript", "random" ]
2011-02-10T16:41:22
2024-06-03T13:50:18
Mirgorod
false
CC BY-SA 4.0
4,960,020
568,975
32,937
null
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Is there a way to generate a random number in a specified range with JavaScript ? For example : a specified range from 1 to 6 were the random number could be either 1, 2, 3, 4, 5, or 6 .
<p>Is there a way to generate a <em>random number</em> in a <em>specified range</em> with JavaScript ?</p> <p><strong>For example</strong>: a specified range from <em>1 to 6</em> were the random number could be either <em>1, 2, 3, 4, 5, or 6</em>.</p>
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2
1133770
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1133770/how-can-i-convert-a-string-to-an-integer-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,133,770
How can I convert a string to an integer in JavaScript?
2,597
2,901,121
32
true
true
[ "javascript", "string", "integer", "data-conversion" ]
2009-07-15T20:22:48
2025-10-05T17:13:52
null
false
CC BY-SA 4.0
1,133,814
null
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How do I convert a string to an integer in JavaScript?
<p>How do I convert a string to an integer in JavaScript?</p>
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1
1414365
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1414365/disable-enable-an-input-with-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,414,365
Disable/enable an input with jQuery?
2,595
2,744,768
19
true
true
[ "javascript", "jquery", "html-input", "disabled-input" ]
2009-09-12T05:21:54
2023-03-29T18:57:52
omg
false
CC BY-SA 4.0
1,414,366
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$input.disabled = true; or $input.disabled = "disabled"; Which is the standard way? And, conversely, how do you enable a disabled input?
<pre><code>$input.disabled = true; </code></pre> <p>or </p> <pre><code>$input.disabled = "disabled"; </code></pre> <p>Which is the standard way? And, conversely, how do you enable a disabled input?</p>
[ { "answerId": 1414366, "score": 4170, "isAccepted": true, "createdAt": "2009-09-12T05:23:34", "ownerDisplayName": "gnarf", "ownerUserId": 91914, "bodyText": "jQuery 1.6+ To change the disabled property you should use the .prop() function. $(\"input\").prop('disabled', true); $(\"input\")...
1
18082
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/18082/validate-decimal-numbers-in-javascript-isnumeric
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
18,082
Validate decimal numbers in JavaScript - IsNumeric()
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true
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[ "javascript", "validation", "numbers" ]
2008-08-20T14:21:13
2024-08-13T12:14:03
Michael Haren
false
CC BY-SA 3.0
1,830,844
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What's the cleanest, most effective way to validate decimal numbers in JavaScript? Bonus points for: Clarity. Solution should be clean and simple. Cross-platform. Test cases: 01. IsNumeric('-1') => true 02. IsNumeric('-1.5') => true 03. IsNumeric('0') => true 04. IsNumeric('0.42') => true 05. IsNumeric('.42') => true 0...
<p>What's the cleanest, most effective way to validate decimal numbers in JavaScript?</p> <p>Bonus points for:</p> <ol> <li>Clarity. Solution should be clean and simple.</li> <li>Cross-platform.</li> </ol> <p>Test cases:</p> <pre><code>01. IsNumeric('-1') =&gt; true 02. IsNumeric('-1.5') =&gt; true 03. IsNu...
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1
1527803
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1527803/generating-random-whole-numbers-in-javascript-in-a-specific-range
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,527,803
Generating random whole numbers in JavaScript in a specific range
2,572
2,145,086
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true
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[ "javascript", "random", "integer" ]
2009-10-06T20:05:41
2025-09-09T17:03:38
zacharyliu
false
CC BY-SA 4.0
1,527,820
133,211
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How can I generate random whole numbers between two specified variables in JavaScript, e.g. x = 4 and y = 8 would output any of 4, 5, 6, 7, 8 ?
<p>How can I generate random whole numbers between two specified variables in JavaScript, e.g. <code>x = 4</code> and <code>y = 8</code> would output any of <code>4, 5, 6, 7, 8</code>?</p>
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1
9229645
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/9229645/remove-duplicate-values-from-a-javascript-array
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
9,229,645
Remove duplicate values from a JavaScript array
2,550
3,431,992
51
true
true
[ "javascript", "jquery", "arrays", "duplicates", "unique" ]
2012-02-10T14:53:22
2025-12-25T19:32:38
kramden88
false
CC BY-SA 4.0
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I have a very simple JavaScript array that may or may not contain duplicates. var names = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"]; I need to remove the duplicates and put the unique values in a new array. I could point to all the code that I've tried but I think it's useless because they don't work. I acc...
<p>I have a very simple JavaScript array that may or may not contain duplicates.</p> <pre><code>var names = [&quot;Mike&quot;,&quot;Matt&quot;,&quot;Nancy&quot;,&quot;Adam&quot;,&quot;Jenny&quot;,&quot;Nancy&quot;,&quot;Carl&quot;]; </code></pre> <p>I need to remove the duplicates and put the unique values in a new arr...
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1
1643227
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1643227/get-selected-text-from-a-drop-down-list-select-box-using-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,643,227
Get selected text from a drop-down list (select box) using jQuery
2,550
2,421,756
35
true
true
[ "javascript", "jquery", "dom", "drop-down-menu", "jquery-selectors" ]
2009-10-29T12:02:09
2021-10-20T14:48:08
haddar
false
CC BY-SA 4.0
1,643,247
170,231
25,715
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
How can I get the selected text (not the selected value) from a drop-down list in jQuery?
<p>How can I get the selected text (not the selected value) from a <strong>drop-down list</strong> in jQuery?</p>
[ { "answerId": 1643247, "score": 4049, "isAccepted": true, "createdAt": "2009-10-29T12:05:38", "ownerDisplayName": "rahul", "ownerUserId": 47738, "bodyText": "$(\"#yourdropdownid option:selected\").text();" } ]
1
149055
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/149055/how-to-format-numbers-as-currency-strings
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
149,055
How to format numbers as currency strings?
2,527
2,963,574
67
true
true
[ "javascript", "formatting", "currency", "number-formatting" ]
2008-09-29T15:00:28
2025-09-26T17:14:08
Daniel Magliola
false
CC BY-SA 4.0
149,150
3,314
32,802
null
null
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I would like to format a price in JavaScript. I'd like a function which takes a float as an argument and returns a string formatted like this: $ 2,500.00 How can I do this?
<p>I would like to format a price in JavaScript. I'd like a function which takes a <code>float</code> as an argument and returns a <code>string</code> formatted like this:</p> <pre><code>$ 2,500.00 </code></pre> <p>How can I do this?</p>
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1
5874652
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/5874652/prop-vs-attr
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
5,874,652
.prop() vs .attr()
2,514
750,952
18
true
true
[ "javascript", "jquery", "dom", "attr", "prop" ]
2011-05-03T19:33:28
2023-12-06T01:53:53
Naftali
false
CC BY-SA 3.0
5,876,747
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So jQuery 1.6 has the new function prop() . $(selector).click(function(){ //instead of: this.getAttribute('style'); //do i use: $(this).prop('style'); //or: $(this).attr('style'); }) or in this case do they do the same thing? And if I do have to switch to using prop() , all the old attr() calls will break if i switch t...
<p>So <a href="http://api.jquery.com/category/version/1.6/" rel="noreferrer">jQuery 1.6</a> has the new function <a href="http://api.jquery.com/prop/" rel="noreferrer"><code>prop()</code></a>.</p> <pre><code>$(selector).click(function(){ //instead of: this.getAttribute('style'); //do i use: $(this).pro...
null
0
2067472
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/2067472/what-is-jsonp-and-why-was-it-created
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
2,067,472
What is JSONP, and why was it created?
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2010-01-14T20:53:48
2023-06-16T19:22:45
Cheeso
false
CC BY-SA 4.0
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I understand JSON, but not JSONP. Wikipedia's document on JSON is (was) the top search result for JSONP. It says this: JSONP or "JSON with padding" is a JSON extension wherein a prefix is specified as an input argument of the call itself. Huh? What call? That doesn't make any sense to me. JSON is a data format. There's...
<p>I understand JSON, but not JSONP. <a href="http://en.wikipedia.org/wiki/JSON" rel="noreferrer">Wikipedia's document on JSON</a> is (was) the top search result for JSONP. It says this:</p> <blockquote> <p>JSONP or "JSON with padding" is a JSON extension wherein a prefix is specified as an input argument of the cal...
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1
3746725
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/3746725/how-to-create-an-array-containing-1-n
gRfaNe5dFEERAlPiJ
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3,746,725
How to create an array containing 1...N
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true
[ "javascript", "arrays", "range" ]
2010-09-19T17:34:17
2026-04-15T06:43:09
Godders
false
CC BY-SA 4.0
3,746,797
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I'm looking for any alternatives to the below for creating a JavaScript array containing 1 through to N where N is only known at runtime. var foo = []; for (var i = 1; i <= N; i++) { foo.push(i); } To me it feels like there should be a way of doing this without the loop.
<p>I'm looking for any alternatives to the below for creating a JavaScript array containing 1 through to N where N is only known at runtime.</p> <pre><code>var foo = []; for (var i = 1; i &lt;= N; i++) { foo.push(i); } </code></pre> <p>To me it feels like there should be a way of doing this without the loop.</p>
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1
5113374
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/5113374/javascript-check-if-variable-exists-is-defined-initialized
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
5,113,374
JavaScript check if variable exists (is defined/initialized)
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2,730,843
31
true
true
[ "javascript", "function", "variables", "initialization", "undefined" ]
2011-02-25T03:44:47
2022-12-11T14:00:19
samliew
false
CC BY-SA 4.0
6,509,422
584,192
79,622
null
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Which method of checking if a variable has been initialized is better/correct? (Assuming the variable could hold anything (string, int, object, function, etc.)) if (elem) { // or !elem or if (typeof elem !== 'undefined') { or if (elem != null) {
<p>Which method of checking if a variable has been initialized is better/correct? (Assuming the variable could hold anything (string, int, object, function, etc.))</p> <pre><code>if (elem) { // or !elem </code></pre> <p>or</p> <pre><code>if (typeof elem !== 'undefined') { </code></pre> <p>or</p> <pre><code>if (elem != ...
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1
610406
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/610406/javascript-equivalent-to-printf-string-format
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
610,406
JavaScript equivalent to printf/String.Format
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true
true
[ "javascript", "printf", "string.format" ]
2009-03-04T12:53:02
2025-08-05T21:13:43
Chris S
false
CC BY-SA 4.0
610,415
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I'm looking for a good JavaScript equivalent of the C/PHP printf() or for C#/Java programmers, String.Format() ( IFormatProvider for .NET). My basic requirement is a thousand separator format for numbers for now, but something that handles lots of combinations (including dates) would be good. I realize Microsoft's Ajax...
<p>I'm looking for a good JavaScript equivalent of the C/PHP <code>printf()</code> or for C#/Java programmers, <code>String.Format()</code> (<code>IFormatProvider</code> for .NET).</p> <p>My basic requirement is a thousand separator format for numbers for now, but something that handles lots of combinations (including...
null
0
3437786
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/3437786/get-the-size-of-the-screen-current-web-page-and-browser-window
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
3,437,786
Get the size of the screen, current web page and browser window
2,469
2,287,104
22
true
true
[ "javascript", "html", "jquery", "layout", "cross-browser" ]
2010-08-09T06:28:58
2024-10-12T05:29:17
turtledove
false
CC BY-SA 4.0
3,437,825
408,393
25,984
null
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null
null
null
How can I get windowWidth , windowHeight , pageWidth , pageHeight , screenWidth , screenHeight , pageX , pageY , screenX , screenY which will work in all major browsers?
<p>How can I get <code>windowWidth</code>, <code>windowHeight</code>, <code>pageWidth</code>, <code>pageHeight</code>, <code>screenWidth</code>, <code>screenHeight</code>, <code>pageX</code>, <code>pageY</code>, <code>screenX</code>, <code>screenY</code> which will work in all major browsers?</p> <p><img src="https://...
null
0
799981
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/799981/document-ready-equivalent-without-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
799,981
$(document).ready equivalent without jQuery
2,464
1,391,610
40
true
true
[ "javascript", "jquery", "pageload" ]
2009-04-28T21:51:11
2026-02-14T02:54:58
FlySwat
false
CC BY-SA 4.0
800,010
1,965
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I have a script that uses $(document).ready , but it doesn't use anything else from jQuery. I'd like to lighten it up by removing the jQuery dependency. How can I implement my own $(document).ready functionality without using jQuery? I know that using window.onload will not be the same, as window.onload fires after all...
<p>I have a script that uses <code>$(document).ready</code>, but it doesn't use anything else from jQuery. I'd like to lighten it up by removing the jQuery dependency.</p> <p>How can I implement my own <code>$(document).ready</code> functionality without using jQuery? I know that using <code>window.onload</code> will...
null
0
1085801
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1085801/get-selected-value-in-dropdown-list-using-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,085,801
Get selected value in dropdown list using JavaScript
2,442
6,117,244
31
true
true
[ "javascript", "html-select" ]
2009-07-06T07:25:06
2023-12-28T14:39:58
Fire Hand
false
CC BY-SA 4.0
1,085,810
127,986
26,586
null
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null
null
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How do I get the selected value from a dropdown list using JavaScript? <form> <select id="ddlViewBy"> <option value="1">test1</option> <option value="2" selected="selected">test2</option> <option value="3">test3</option> </select> </form>
<p>How do I get the selected value from a dropdown list using JavaScript?</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false"> <div class="snippet-code"> <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;form&gt; &lt;select id="ddlViewBy"&gt; ...
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1
8073673
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/8073673/how-can-i-add-new-array-elements-at-the-beginning-of-an-array-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
8,073,673
How can I add new array elements at the beginning of an array in JavaScript?
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1,754,189
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true
true
[ "javascript", "arrays" ]
2011-11-10T00:35:22
2025-04-15T21:58:06
Moon
false
CC BY-SA 4.0
8,073,687
309,343
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I have a need to add or prepend elements at the beginning of an array. For example, if my array looks like below: [23, 45, 12, 67] And the response from my AJAX call is 34 , I want the updated array to be like the following: [34, 23, 45, 12, 67] Currently I am planning to do it like this: var newArray = []; newArray.pu...
<p>I have a need to add or prepend elements at the beginning of an array.</p> <p>For example, if my array looks like below:</p> <pre><code>[23, 45, 12, 67] </code></pre> <p>And the response from my AJAX call is <code>34</code>, I want the updated array to be like the following:</p> <pre><code>[34, 23, 45, 12, 67] </cod...
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1
306583
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/306583/how-to-get-the-children-of-the-this-selector
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
306,583
How to get the children of the $(this) selector?
2,423
1,997,844
19
true
true
[ "javascript", "jquery", "jquery-selectors" ]
2008-11-20T19:44:05
2024-07-31T09:36:31
Alex
false
CC BY-SA 4.0
306,904
16,974
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null
I have a layout similar to this, and would like to use a jQuery selector to select the child img inside the div on click. <div id="..."> <img src="..."> </div> To get the div , I've got this selector: $(this) How can I get the child img using a selector?
<p>I have a layout similar to this, and would like to use a <code>jQuery</code> selector to select the child <code>img</code> inside the <code>div</code> on click.</p> <pre class="lang-html prettyprint-override"><code>&lt;div id=&quot;...&quot;&gt; &lt;img src=&quot;...&quot;&gt; &lt;/div&gt; </code></pre> <p>To get ...
[ { "answerId": 306904, "score": 2986, "isAccepted": true, "createdAt": "2008-11-20T21:27:29", "ownerDisplayName": "Simon", "ownerUserId": 33036, "bodyText": "The jQuery constructor accepts a 2nd parameter called context which can be used to override the context of the selection. jQuery(\"...
1
287903
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/287903/how-can-i-guarantee-that-my-enums-definition-doesnt-change-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
287,903
How can I guarantee that my enums definition doesn't change in JavaScript?
2,396
1,289,445
50
true
true
[ "javascript" ]
2008-11-13T19:09:06
2023-09-11T11:28:22
David Citron
false
CC BY-SA 4.0
5,040,502
5,309
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null
Would the following make the objects fulfil all characteristics that enums have in JavaScript? Something like: my.namespace.ColorEnum = { RED : 0, GREEN : 1, BLUE : 2 } // later on if(currentColor == my.namespace.ColorEnum.RED) { // whatever } Or is there some other way I can do this?
<p>Would the following make the objects fulfil all characteristics that enums have in JavaScript? Something like:</p> <pre class="lang-js prettyprint-override"><code>my.namespace.ColorEnum = { RED : 0, GREEN : 1, BLUE : 2 } // later on if(currentColor == my.namespace.ColorEnum.RED) { // whatever } </code></p...
null
0
31079081
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/31079081/how-can-i-programmatically-navigate-using-react-router
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
31,079,081
How can I programmatically navigate using React Router?
2,376
1,817,076
50
true
true
[ "javascript", "reactjs", "react-router" ]
2015-06-26T17:38:51
2026-02-06T10:14:42
George Mauer
false
CC BY-SA 4.0
42,121,109
5,056
123,156
null
null
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null
null
null
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null
With React Router , I can use the Link element to create links which are natively handled by React Router. I see internally it calls this.context.transitionTo(...) . I want to do navigation. Not from a link, but from a dropdown selection (as an example). How can I do this in code? What is this.context ? I saw the Navig...
<p>With <a href="https://reactrouter.com/" rel="noreferrer">React Router</a>, I can use the <code>Link</code> element to create links which are natively handled by React Router.</p> <p>I see internally it calls <code>this.context.transitionTo(...)</code>.</p> <p>I want to do navigation. Not from a link, but from a drop...
[ { "answerId": 42121109, "score": 2637, "isAccepted": true, "createdAt": "2017-02-08T18:39:41", "ownerDisplayName": "Paul S", "ownerUserId": 444829, "bodyText": "React Router v6.6.1 with useNavigate The useHistory() hook is now deprecated. If you are using React Router 6, the proper way t...
1
8511281
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/8511281/check-if-a-value-is-an-object-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
8,511,281
Check if a value is an object in JavaScript
2,337
2,528,212
59
true
true
[ "javascript", "types", "javascript-objects" ]
2011-12-14T20:35:47
2025-01-03T16:20:55
Danny Fox
false
CC BY-SA 4.0
8,511,332
1,091,828
41,169
null
null
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null
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null
null
How do you check if a value is an object in JavaScript?
<p>How do you check if a value is an object in JavaScript?</p>
[ { "answerId": 8511350, "score": 2624, "isAccepted": false, "createdAt": "2011-12-14T20:40:51", "ownerDisplayName": "Chuck", "ownerUserId": 50742, "bodyText": "If typeof x === 'object' , x is an object (except a function) or null . If you want null , arrays, and functions to be excluded, ...
1
242813
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/242813/are-double-quotes-and-single-quotes-interchangeable-for-string-literals-in-javas
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
242,813
Are double quotes and single quotes interchangeable for string literals in JavaScript?
2,333
761,574
24
true
true
[ "javascript", "string" ]
2008-10-28T10:34:35
2025-11-01T04:02:18
aemkei
false
CC BY-SA 4.0
242,833
28,150
11,235
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Consider the following two alternatives: console.log("double"); console.log('single'); The former uses double quotes around the string, whereas the latter uses single quotes around the string. I see more and more JavaScript libraries out there using single quotes when handling strings. Are these two usages interchangea...
<p>Consider the following two alternatives:</p> <ul> <li><code>console.log(&quot;double&quot;);</code></li> <li><code>console.log('single');</code></li> </ul> <p>The former uses double quotes around the string, whereas the latter uses single quotes around the string.</p> <p>I see more and more JavaScript libraries out ...
null
0
2641347
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/2641347/short-circuit-array-foreach-like-calling-break
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
2,641,347
Short circuit Array.forEach like calling break
2,249
1,908,152
32
true
true
[ "javascript", "arrays", "foreach" ]
2010-04-14T21:57:31
2025-09-19T09:04:15
Scott Klarenbach
false
CC BY-SA 4.0
2,641,374
140,811
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[1,2,3].forEach(function(el) { if(el === 1) break; }); How can I do this using the new forEach method in JavaScript? I've tried return; , return false; and break . break crashes and return does nothing but continue iteration.
<pre><code>[1,2,3].forEach(function(el) { if(el === 1) break; }); </code></pre> <p>How can I do this using the new <code>forEach</code> method in JavaScript? I've tried <code>return;</code>, <code>return false;</code> and <code>break</code>. <code>break</code> crashes and <code>return</code> does nothing but conti...
[ { "answerId": 2641374, "score": 2931, "isAccepted": true, "createdAt": "2010-04-14T22:02:14", "ownerDisplayName": "bobince", "ownerUserId": 18936, "bodyText": "There's no built-in ability to break in forEach . To interrupt execution you would have to throw an exception of some sort. eg. ...
1
500431
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/500431/what-is-the-scope-of-variables-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
500,431
What is the scope of variables in JavaScript?
2,223
585,767
27
true
true
[ "javascript", "function", "variables", "scope", "var" ]
2009-02-01T08:27:19
2021-06-28T11:13:30
lYriCAlsSH
false
CC BY-SA 3.0
500,459
60,102
58,197
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
What is the scope of variables in javascript? Do they have the same scope inside as opposed to outside a function? Or does it even matter? Also, where are the variables stored if they are defined globally?
<p>What is the scope of variables in javascript? Do they have the same scope inside as opposed to outside a function? Or does it even matter? Also, where are the variables stored if they are defined globally?</p>
[ { "answerId": 500459, "score": 2687, "isAccepted": true, "createdAt": "2009-02-01T08:58:50", "ownerDisplayName": "Kenan Banks", "ownerUserId": 43089, "bodyText": "TLDR JavaScript has lexical (also called static) scoping and closures. This means you can tell the scope of an identifier by ...
1
1353684
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1353684/detecting-an-invalid-date-date-instance-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,353,684
Detecting an "invalid date" Date instance in JavaScript
2,222
1,665,691
56
true
true
[ "javascript", "date" ]
2009-08-30T11:34:40
2025-08-27T09:46:17
orip
false
CC BY-SA 3.0
1,353,711
37,020
76,144
null
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I'd like to tell the difference between valid and invalid date objects in JS, but couldn't figure out how: var d = new Date("foo"); console.log(d.toString()); // shows 'Invalid Date' console.log(typeof d); // shows 'object' console.log(d instanceof Date); // shows 'true' Any ideas for writing an isValidDate function? A...
<p>I'd like to tell the difference between valid and invalid date objects in JS, but couldn't figure out how:</p> <pre><code>var d = new Date("foo"); console.log(d.toString()); // shows 'Invalid Date' console.log(typeof d); // shows 'object' console.log(d instanceof Date); // shows 'true' </code></pre> <p>Any ideas f...
null
0
3102819
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/3102819/disable-same-origin-policy-in-chrome
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
3,102,819
Disable same origin policy in Chrome
2,218
3,852,788
39
true
true
[ "javascript", "ajax", "google-chrome" ]
2010-06-23T15:00:21
2026-07-07T07:56:54
Landon Kuhn
false
CC BY-SA 4.0
3,177,718
1,785
79,061
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
Is there any way to disable the Same-origin policy on Google's Chrome browser?
<p>Is there any way to disable the <a href="https://en.wikipedia.org/wiki/Same_origin_policy" rel="noreferrer">Same-origin policy</a> on Google's <a href="http://en.wikipedia.org/wiki/Google_Chrome" rel="noreferrer">Chrome</a> browser?</p>
null
0
1232040
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1232040/how-do-i-empty-an-array-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,232,040
How do I empty an array in JavaScript?
2,192
4,412,952
17
true
true
[ "javascript", "arrays" ]
2009-08-05T09:08:39
2024-09-18T07:00:21
akano1
false
CC BY-SA 3.0
1,232,046
149,738
41,952
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
Is there a way to empty an array and if so possibly with .remove() ? For instance, A = [1,2,3,4]; How can I empty that?
<p>Is there a way to empty an array and if so possibly with <code>.remove()</code>?</p> <p>For instance, </p> <pre><code>A = [1,2,3,4]; </code></pre> <p>How can I empty that?</p>
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2
5062614
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/5062614/how-to-decide-when-to-use-node-js
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
5,062,614
How to decide when to use Node.js?
2,190
590,176
17
true
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[ "javascript", "node.js", "web-applications" ]
2011-02-21T05:20:51
2026-07-06T17:30:02
Legend
false
CC BY-SA 4.0
5,062,670
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I am new to this kind of stuff, but lately I've been hearing a lot about how good Node.js is. Considering how much I love working with jQuery and JavaScript in general, I can't help but wonder how to decide when to use Node.js. The web application I have in mind is something like Bitly - takes some content, archives it...
<p>I am new to this kind of stuff, but lately I've been hearing a lot about how good <a href="http://en.wikipedia.org/wiki/Node.js" rel="nofollow noreferrer">Node.js</a> is. Considering how much I love working with jQuery and JavaScript in general, I can't help but wonder how to decide when to use Node.js. The web appl...
null
0
3216013
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/3216013/get-the-last-item-in-an-array
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
3,216,013
Get the last item in an array
2,186
3,671,512
64
true
true
[ "javascript", "arrays" ]
2010-07-09T19:45:06
2025-07-17T06:39:28
balexander
false
CC BY-SA 4.0
3,216,041
316,429
24,669
null
null
null
null
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Here is my JavaScript code so far: var linkElement = document.getElementById("BackButton"); var loc_array = document.location.href.split('/'); var newT = document.createTextNode(unescape(capWords(loc_array[loc_array.length-2]))); linkElement.appendChild(newT); Currently it takes the second to last item in the array fro...
<p>Here is my JavaScript code so far:</p> <pre><code>var linkElement = document.getElementById("BackButton"); var loc_array = document.location.href.split('/'); var newT = document.createTextNode(unescape(capWords(loc_array[loc_array.length-2]))); linkElement.appendChild(newT); </code></pre> <p>Currently it takes th...
[ { "answerId": 3216041, "score": 2590, "isAccepted": true, "createdAt": "2010-07-09T19:48:58", "ownerDisplayName": "Aaron Butacov", "ownerUserId": 365695, "bodyText": "if (loc_array[loc_array.length - 1] === 'index.html') { // do something } else { // something else } In the event that yo...
2
767486
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/767486/how-do-i-check-if-a-variable-is-an-array-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
767,486
How do I check if a variable is an array in JavaScript?
2,185
1,380,175
26
true
true
[ "javascript", "arrays", "list", "variables" ]
2009-04-20T09:02:59
2024-07-11T04:04:35
Andy McCluggage
false
CC BY-SA 4.0
26,633,883
3,362
38,978
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
How do I check if a variable is an array in JavaScript? if (variable.constructor == Array)
<p>How do I check if a variable is an array in JavaScript?</p> <pre><code>if (variable.constructor == Array) </code></pre>
[ { "answerId": 26633883, "score": 2069, "isAccepted": true, "createdAt": "2014-10-29T15:07:05", "ownerDisplayName": "jemiloii", "ownerUserId": 630496, "bodyText": "There are several ways of checking if an variable is an array or not. The best solution is the one you have chosen. variable....
1
572897
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/572897/how-does-javascript-prototype-work
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
572,897
How does JavaScript .prototype work?
2,184
521,676
26
true
true
[ "javascript", "dynamic-languages", "prototype-oriented" ]
2009-02-21T12:31:18
2024-05-17T05:14:24
John Leidegren
false
CC BY-SA 4.0
572,996
58,961
61,382
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I'm not that into dynamic programming languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works? var obj = new Object(); obj.prototype.test = function() { alert('Hello?'); }; var obj2 = new obj(); obj2.test(); I reme...
<p>I'm not that into dynamic programming languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works?</p> <pre><code>var obj = new Object(); obj.prototype.test = function() { alert('Hello?'); }; var obj2 = new obj(); o...
[ { "answerId": 4778408, "score": 1834, "isAccepted": false, "createdAt": "2011-01-24T03:42:35", "ownerDisplayName": "stivlo", "ownerUserId": 445543, "bodyText": "In a language implementing classical inheritance like Java, C# or C++ you start by creating a class--a blueprint for your objec...
1
4459379
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/4459379/preview-an-image-before-it-is-uploaded
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
4,459,379
Preview an image before it is uploaded
2,175
1,890,132
30
true
true
[ "javascript", "jquery", "file-upload" ]
2010-12-16T09:51:32
2024-08-20T12:09:16
Simbian
false
CC BY-SA 3.0
4,459,419
518,838
21,953
null
null
null
null
null
null
null
null
null
null
null
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null
null
I want to be able to preview a file (image) before it is uploaded. The preview action should be executed all in the browser without using Ajax to upload the image. How can I do this?
<p>I want to be able to preview a file (image) before it is uploaded. The preview action should be executed all in the browser without using Ajax to upload the image.</p> <p>How can I do this?</p>
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1
7486085
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/7486085/how-to-create-a-copy-of-a-javascript-array-instead-of-a-reference
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
7,486,085
How to create a copy of a JavaScript array instead of a reference?
2,165
1,332,765
40
true
true
[ "javascript", "arrays", "deep-copy", "pass-by-value" ]
2011-09-20T13:38:08
2026-05-04T10:12:20
Dan
false
CC BY-SA 4.0
7,486,130
944,555
21,937
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When copying an array in JavaScript to another array: var arr1 = ['a','b','c']; var arr2 = arr1; arr2.push('d'); console.log(arr1); //= ['a','b','c','d'] I realized that arr2 refers to the same array as arr1 , rather than a new, independent array. How can I copy the array to get two independent arrays?
<p>When copying an array in JavaScript to another array:</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false" data-babel-preset-react="false" data-babel-preset-ts="false"> <div class="snippet-code"> <pre class="snippet-code-js lang-js prettyprint-override"><code>var arr1 =...
[ { "answerId": 7486130, "score": 3156, "isAccepted": true, "createdAt": "2011-09-20T13:41:21", "ownerDisplayName": "Saket", "ownerUserId": 946312, "bodyText": "Use this: let oldArray = [1, 2, 3, 4, 5]; let newArray = oldArray.slice(); console.log({newArray}); Basically, the slice() operat...
1
7364150
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/7364150/search-an-array-of-javascript-objects-for-an-object-with-a-matching-value
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
7,364,150
Search an array of JavaScript objects for an object with a matching value
2,160
2,542,696
37
true
true
[ "javascript", "arrays", "javascript-objects" ]
2011-09-09T15:42:29
2024-09-02T17:18:01
thugsb
false
CC BY-SA 4.0
35,398,031
614,566
23,486
null
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I've got an array: myArray = [{'id':'73','foo':'bar'},{'id':'45','foo':'bar'}, etc.] I'm unable to change the structure of the array. I'm being passed an id of 45 , and I want to get 'bar' for that object in the array. How do I do this in JavaScript or using jQuery?
<p>I've got an array:</p> <pre><code>myArray = [{'id':'73','foo':'bar'},{'id':'45','foo':'bar'}, etc.] </code></pre> <p>I'm unable to change the structure of the array. I'm being passed an id of <code>45</code>, and I want to get <code>'bar'</code> for that object in the array. </p> <p>How do I do this in JavaScript...
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2
957537
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/957537/how-can-i-display-a-javascript-object
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
957,537
How can I display a JavaScript object?
2,151
2,639,962
40
true
true
[ "javascript", "serialization", "javascript-objects" ]
2009-06-05T19:01:59
2024-11-07T11:17:08
maxjackie
false
CC BY-SA 4.0
957,633
118,061
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null
How do I display the content of a JavaScript object in a string format like when we alert a variable? The same formatted way I want to display an object.
<p>How do I display the content of a JavaScript object in a string format like when we <code>alert</code> a variable?</p> <p>The same formatted way I want to display an object.</p>
[ { "answerId": 4293047, "score": 2500, "isAccepted": false, "createdAt": "2010-11-27T17:52:28", "ownerDisplayName": "Sandeep", "ownerUserId": 218857, "bodyText": "Use native JSON.stringify method. Works with nested objects and all major browsers support this method. str = JSON.stringify(o...
1
2496710
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/2496710/writing-to-files-in-node-js
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
2,496,710
Writing to files in Node.js
2,128
2,189,346
19
true
true
[ "javascript", "node.js", "file", "express", "fs" ]
2010-03-23T00:25:02
2024-12-06T15:31:07
Gjorgji
false
CC BY-SA 4.0
2,497,040
282,329
23,164
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
I've been trying to find a way to write to a file when using Node.js, but with no success. How can I do that?
<p>I've been trying to find a way to write to a file when using Node.js, but with no success. How can I do that?</p>
[ { "answerId": 2497040, "score": 3030, "isAccepted": true, "createdAt": "2010-03-23T01:50:15", "ownerDisplayName": "Brian McKenna", "ownerUserId": 108359, "bodyText": "There are a lot of details in the File System API . The most common way is: const fs = require('fs'); fs.writeFile(\"/tmp...
1
22876978
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/22876978/loop-inside-react-jsx
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
22,876,978
Loop inside React JSX
2,105
2,212,247
88
true
true
[ "javascript", "reactjs", "jsx" ]
2014-04-05T05:29:28
2025-02-11T12:26:59
B Robster
false
CC BY-SA 4.0
22,877,049
652,693
42,213
null
null
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null
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I'm trying to do something like the following in React JSX (where ObjectRow is a separate component): <tbody> for (var i=0; i < numrows; i++) { <ObjectRow/> } </tbody> I realize and understand why this isn't valid JSX, since JSX maps to function calls. However, coming from template land and being new to JSX, I am unsur...
<p>I'm trying to do something like the following in React JSX (where ObjectRow is a separate component):</p> <pre><code>&lt;tbody&gt; for (var i=0; i &lt; numrows; i++) { &lt;ObjectRow/&gt; } &lt;/tbody&gt; </code></pre> <p>I realize and understand why this isn't valid JSX, since JSX maps to function c...
[ { "answerId": 22877049, "score": 1830, "isAccepted": true, "createdAt": "2014-04-05T05:39:46", "ownerDisplayName": "Sophie Alpert", "ownerUserId": 49485, "bodyText": "Think of it like you're just calling JavaScript functions. You can't use a for loop where the arguments to a function cal...
1
500504
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/500504/why-is-using-for-in-for-array-iteration-a-bad-idea
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
500,504
Why is using "for...in" for array iteration a bad idea?
2,102
1,087,399
28
true
true
[ "javascript", "arrays", "loops", "for-loop", "iteration" ]
2009-02-01T09:46:38
2023-05-16T13:05:57
lYriCAlsSH
false
CC BY-SA 4.0
500,531
60,102
58,197
null
null
null
null
null
null
null
null
null
null
null
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null
null
null
I've been told not to use for...in with arrays in JavaScript. Why not?
<p>I've been told not to use <code>for...in</code> with arrays in JavaScript. Why not?</p>
[ { "answerId": 500531, "score": 1742, "isAccepted": true, "createdAt": "2009-02-01T10:08:34", "ownerDisplayName": "Kenan Banks", "ownerUserId": 43089, "bodyText": "The reason is that one construct: var a = []; // Create a new empty array. a[5] = 5; // Perfectly legal JavaScript that resiz...
1
1144805
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1144805/scroll-to-the-top-of-the-page-using-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,144,805
Scroll to the top of the page using JavaScript?
2,088
2,586,692
50
true
true
[ "javascript", "scroll" ]
2009-07-17T17:59:09
2023-10-06T20:55:14
KingNestor
false
CC BY-SA 4.0
1,145,012
64,878
68,490
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
How do I scroll to the top of the page using JavaScript? The scrollbar instantly jumping to the top of the page is desirable too as I'm not looking to achieve smooth scrolling.
<p>How do I scroll to the top of the page using JavaScript? The scrollbar instantly jumping to the top of the page is desirable too as I'm not looking to achieve smooth scrolling.</p>
[ { "answerId": 1145012, "score": 2732, "isAccepted": true, "createdAt": "2009-07-17T18:42:35", "ownerDisplayName": "SavoryBytes", "ownerUserId": 131944, "bodyText": "If you don't need the change to animate then you don't need to use any special plugins - I'd just use the native JavaScript...
2
27732209
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/27732209/turning-off-an-eslint-rule-for-a-specific-line
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
27,732,209
Turning off an ESLint rule for a specific line
2,071
1,865,480
15
true
true
[ "javascript", "jshint", "eslint" ]
2015-01-01T15:47:47
2026-03-04T03:52:43
runtimeZero
false
CC BY-SA 4.0
29,592,334
2,117,019
28,476
null
null
null
null
null
null
null
null
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null
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null
null
null
In order to turn off a linting rule for a particular line in JSHint, we use the following rule: /* jshint ignore:start*/ $scope.someVar = ConstructorFunction(); /* jshint ignore:end */ Is there an equivalent of the above for ESLint?
<p>In order to turn off a linting rule for a particular line in JSHint, we use the following rule:</p> <pre><code>/* jshint ignore:start*/ $scope.someVar = ConstructorFunction(); /* jshint ignore:end */ </code></pre> <p>Is there an equivalent of the above for ESLint?</p>
[ { "answerId": 29592334, "score": 3240, "isAccepted": true, "createdAt": "2015-04-12T17:27:38", "ownerDisplayName": "goofballLogic", "ownerUserId": 275501, "bodyText": "To disable the next line: // eslint-disable-next-line no-use-before-define var thing = new Thing(); Or use the single li...
1
2450954
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/2450954/how-to-randomize-shuffle-a-javascript-array
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
2,450,954
How to randomize (shuffle) a JavaScript array?
2,068
1,793,713
58
true
true
[ "javascript", "arrays", "random", "shuffle" ]
2010-03-15T22:37:11
2025-03-21T07:11:59
Ali
false
CC BY-SA 4.0
2,450,976
49,153
268,312
null
null
null
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null
null
null
null
null
null
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null
null
I have an array like this: var arr1 = ["a", "b", "c", "d"]; How can I randomize / shuffle it?
<p>I have an array like this:</p> <pre><code>var arr1 = ["a", "b", "c", "d"]; </code></pre> <p>How can I randomize / shuffle it?</p>
[ { "answerId": 2450976, "score": 2628, "isAccepted": true, "createdAt": "2010-03-15T22:41:10", "ownerDisplayName": "ChristopheD", "ownerUserId": 81179, "bodyText": "The de-facto unbiased shuffle algorithm is the Fisher–Yates (aka Knuth) Shuffle . You can see a great visualization here . f...
1
175739
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/175739/how-can-i-check-if-a-string-is-a-valid-number
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
175,739
How can I check if a string is a valid number?
2,051
1,979,976
56
true
true
[ "javascript", "validation", "numeric" ]
2008-10-06T19:12:52
2026-01-15T18:59:05
Electrons_Ahoy
false
CC BY-SA 4.0
175,787
19,074
39,141
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
I'm hoping there's something in the same conceptual space as the old VB6 IsNumeric() function?
<p>I'm hoping there's something in the same conceptual space as the old VB6 <code>IsNumeric()</code> function?</p>
[ { "answerId": 175787, "score": 3317, "isAccepted": true, "createdAt": "2008-10-06T19:24:20", "ownerDisplayName": "Dan", "ownerUserId": 17121, "bodyText": "2nd October 2020: note that many bare-bones approaches are fraught with subtle bugs (eg. whitespace, implicit partial parsing, radix,...
1
9682092
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/9682092/how-does-data-binding-work-in-angularjs
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
9,682,092
How does data binding work in AngularJS?
2,050
366,118
14
true
true
[ "javascript", "angularjs", "data-binding" ]
2012-03-13T10:16:37
2018-11-05T12:56:41
Pashec
false
CC BY-SA 3.0
9,693,933
168,367
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null
null
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How does data binding work in the AngularJS framework? I haven't found technical details on their site . It's more or less clear how it works when data is propagated from view to model. But how does AngularJS track changes of model properties without setters and getters? I found that there are JavaScript watchers that ...
<p>How does data binding work in the <code>AngularJS</code> framework?</p> <p>I haven't found technical details on <a href="http://angularjs.org" rel="noreferrer">their site</a>. It's more or less clear how it works when data is propagated from view to model. But how does AngularJS track changes of model properties wi...
[ { "answerId": 9693933, "score": 2763, "isAccepted": true, "createdAt": "2012-03-13T23:47:35", "ownerDisplayName": "Misko Hevery", "ownerUserId": 192810, "bodyText": "AngularJS remembers the value and compares it to a previous value. This is basic dirty-checking. If there is a change in v...
1
126100
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/126100/how-to-efficiently-count-the-number-of-keys-properties-of-an-object-in-javascrip
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
126,100
How to efficiently count the number of keys/properties of an object in JavaScript
2,046
1,092,306
19
true
true
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2008-09-24T08:56:21
2025-01-16T02:30:15
mjs
false
CC BY-SA 4.0
4,889,658
11,543
65,593
null
null
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null
null
null
null
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null
null
null
null
null
null
What’s the fastest way to count the number of keys/properties of an object? Is it possible to do this without iterating over the object, i.e., without doing: var count = 0; for (k in myobj) if (myobj.hasOwnProperty(k)) ++count; (Firefox did provide a magic __count__ property, but this was removed somewhere around versi...
<p>What’s the fastest way to count the number of keys/properties of an object? Is it possible to do this without iterating over the object, i.e., without doing:</p> <pre><code>var count = 0; for (k in myobj) if (myobj.hasOwnProperty(k)) ++count; </code></pre> <p>(Firefox did provide a magic <code>__count__</code> prope...
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1
1584370
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1584370/how-to-merge-two-arrays-in-javascript-and-de-duplicate-items
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,584,370
How to merge two arrays in JavaScript and de-duplicate items
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2,257,530
93
true
true
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2009-10-18T08:34:57
2025-05-20T15:58:46
Vijjendra
false
CC BY-SA 3.0
1,584,377
165,873
25,301
null
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I have two JavaScript arrays: var array1 = ["Vijendra","Singh"]; var array2 = ["Singh", "Shakya"]; I want the output to be: var array3 = ["Vijendra","Singh","Shakya"]; The output array should have repeated words removed. How do I merge two arrays in JavaScript so that I get only the unique items from each array in the ...
<p>I have two JavaScript arrays:</p> <pre><code>var array1 = ["Vijendra","Singh"]; var array2 = ["Singh", "Shakya"]; </code></pre> <p>I want the output to be:</p> <pre><code>var array3 = ["Vijendra","Singh","Shakya"]; </code></pre> <p>The output array should have repeated words removed.</p> <p>How do I merge two a...
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1
455338
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/455338/how-do-i-check-if-an-object-has-a-key-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
455,338
How do I check if an object has a key in JavaScript?
2,032
2,339,104
2
true
true
[ "javascript", "object" ]
2009-01-18T15:42:58
2020-01-09T10:52:24
kevin
true
null
455,366
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
Which is the right thing to do? if (myObj['key'] == undefined) or if (myObj['key'] == null) or if (myObj['key'])
<p>Which is the right thing to do?</p> <pre><code>if (myObj['key'] == undefined) </code></pre> <p>or</p> <pre><code>if (myObj['key'] == null) </code></pre> <p>or</p> <pre><code>if (myObj['key']) </code></pre>
[ { "answerId": 455366, "score": 3511, "isAccepted": true, "createdAt": "2009-01-18T16:03:00", "ownerDisplayName": "ForYourOwnGood", "ownerUserId": 48728, "bodyText": "Try the JavaScript in operator . if ('key' in myObj) And the inverse. if (!('key' in myObj)) Be careful! The in operator m...
1
446594
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/446594/abort-ajax-requests-using-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
446,594
Abort Ajax requests using jQuery
2,007
732,598
18
true
true
[ "javascript", "jquery", "ajax" ]
2009-01-15T12:45:18
2024-04-09T01:03:07
lukewm
false
CC BY-SA 4.0
446,626
47,831
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null
null
null
null
null
null
null
null
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null
null
null
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null
null
Is it possible that using jQuery, I cancel/abort an Ajax request that I have not yet received the response from?
<p>Is it possible that using jQuery, I <strong>cancel/abort an Ajax request</strong> that I have not yet received the response from?</p>
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1
1168807
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1168807/how-can-i-add-a-key-value-pair-to-a-javascript-object
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,168,807
How can I add a key/value pair to a JavaScript object?
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4,248,208
17
true
true
[ "javascript", "object-literal" ]
2009-07-22T23:21:51
2025-01-01T13:58:53
James Skidmore
false
CC BY-SA 4.0
1,168,814
95,267
50,468
null
null
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Here is my object literal: var obj = {key1: value1, key2: value2}; How can I add field key3 with value3 to the object?
<p>Here is my object literal:</p> <pre><code>var obj = {key1: value1, key2: value2}; </code></pre> <p>How can I add field <code>key3</code> with <code>value3</code> to the object?</p>
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1
494035
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/494035/how-do-you-use-a-variable-in-a-regular-expression
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
494,035
How do you use a variable in a regular expression?
1,982
1,363,277
29
true
true
[ "javascript", "regex" ]
2009-01-30T00:11:05
2025-09-25T12:46:29
JC Grubbs
false
CC BY-SA 4.0
494,046
4,541
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I would like to create a String.replaceAll() method in JavaScript and think using a regex would be the most terse way to do it. However, I can't figure out how to pass a variable into a regex. I can do this already which will replace all the instances of "B" with "A" . "ABABAB".replace(/B/g, "A"); But I want to do some...
<p>I would like to create a <code>String.replaceAll()</code> method in JavaScript and think using a regex would be the most terse way to do it. However, I can't figure out how to pass a variable into a regex. I can do this already which will replace all the instances of <code>&quot;B&quot;</code> with <code>&quot;A&q...
[ { "answerId": 494046, "score": 2446, "isAccepted": true, "createdAt": "2009-01-30T00:15:40", "ownerDisplayName": "Eric Wendelin", "ownerUserId": 25066, "bodyText": "Instead of using the /\\sREGEX\\s/g syntax, you can construct a new RegExp object: // variable == 'REGEX' let re = new RegE...
1
19590865
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/19590865/from-an-array-of-objects-extract-value-of-a-property-as-array
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
19,590,865
From an array of objects, extract value of a property as array
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2,036,475
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true
true
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2013-10-25T13:13:03
2025-02-15T16:44:54
hyde
false
CC BY-SA 4.0
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1,717,300
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I have JavaScript object array with the following structure: objArray = [ { foo: 1, bar: 2}, { foo: 3, bar: 4}, { foo: 5, bar: 6} ]; I want to extract a field from each object, and get an array containing the values, for example field foo would give array [ 1, 3, 5 ] . I can do this with this trivial approach: function...
<p>I have JavaScript object array with the following structure:</p> <pre><code>objArray = [ { foo: 1, bar: 2}, { foo: 3, bar: 4}, { foo: 5, bar: 6} ]; </code></pre> <p>I want to extract a field from each object, and get an array containing the values, for example field <code>foo</code> would give array <code>[ 1, 3, ...
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1
57803
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/57803/how-to-convert-decimal-to-hexadecimal-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
57,803
How to convert decimal to hexadecimal in JavaScript
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1,548,913
31
true
true
[ "javascript", "hex", "number-formatting", "radix" ]
2008-09-11T22:26:58
2024-10-08T08:44:52
Luke Smith
false
CC BY-SA 4.0
57,805
5,556
24,394
null
null
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null
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How do you convert decimal values to their hexadecimal equivalent in JavaScript?
<p>How do you convert decimal values to their hexadecimal equivalent in JavaScript?</p>
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1
3514784
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/3514784/how-to-detect-a-mobile-device-using-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
3,514,784
How to detect a mobile device using jQuery
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1,977,006
65
true
true
[ "javascript", "jquery", "mobile", "browser-detection" ]
2010-08-18T17:22:22
2024-01-18T23:00:54
superUntitled
false
CC BY-SA 4.0
3,540,295
54,259
22,622
null
null
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Is there a way to detect whether or not a user is using a mobile device in jQuery? Something similar to the CSS @media attribute? I would like to run a different script if the browser is on a handheld device. The jQuery $.browser function is not what I am looking for.
<p>Is there a way to detect whether or not a user is using a mobile device in jQuery? Something similar to the CSS <code>@media</code> attribute? I would like to run a different script if the browser is on a handheld device.</p> <p>The jQuery <code>$.browser</code> function is not what I am looking for.</p>
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1
436411
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/436411/where-should-i-put-script-tags-in-html-markup
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
436,411
Where should I put <script> tags in HTML markup?
1,960
912,028
22
true
true
[ "javascript", "html" ]
2009-01-12T18:15:54
2024-10-12T13:03:20
mipadi
false
CC BY-SA 4.0
24,070,373
28,804
414,647
null
null
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null
null
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When embedding JavaScript in an HTML document, where is the proper place to put the <script> tags and included JavaScript? I seem to recall that you are not supposed to place these in the <head> section, but placing at the beginning of the <body> section is bad, too, since the JavaScript will have to be parsed before t...
<p>When embedding JavaScript in an HTML document, where is the proper place to put the <code>&lt;script&gt;</code> tags and included JavaScript? I seem to recall that you are not supposed to place these in the <code>&lt;head&gt;</code> section, but placing at the beginning of the <code>&lt;body&gt;</code> section is ba...
[ { "answerId": 24070373, "score": 2472, "isAccepted": true, "createdAt": "2014-06-05T21:20:51", "ownerDisplayName": "Bart", "ownerUserId": 454531, "bodyText": "Here's what happens when a browser loads a website with a <script> tag on it: Fetch the HTML page (e.g. index.html ) Begin parsin...
1
12694530
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/12694530/what-is-typescript-and-why-should-i-use-it-instead-of-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
12,694,530
What is TypeScript and why should I use it instead of JavaScript?
1,939
697,583
5
true
true
[ "javascript", "typescript" ]
2012-10-02T16:37:58
2026-07-14T10:29:05
Mohammed Thabet
false
CC BY-SA 4.0
12,694,578
353,953
21,709
null
null
null
null
null
null
null
null
null
null
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null
null
What is the TypeScript language? What can it do that JavaScript or available libraries cannot do, that would give me reason to consider it?
<p>What is the TypeScript language? What can it do that JavaScript or available libraries cannot do, that would give me reason to consider it?</p>
[ { "answerId": 12694578, "score": 1441, "isAccepted": true, "createdAt": "2012-10-02T16:41:28", "ownerDisplayName": "Paul Dixon", "ownerUserId": 6521, "bodyText": "I originally wrote this answer when TypeScript was still hot-off-the-presses. Five years later, this is an OK overview, but l...
1
1279957
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1279957/how-to-move-an-element-into-another-element
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,279,957
How to move an element into another element
1,938
1,465,153
16
true
true
[ "javascript", "jquery", "html" ]
2009-08-14T20:14:45
2024-10-08T08:21:47
Mark Richman
false
CC BY-SA 4.0
1,279,963
134,484
29,830
null
null
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null
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I would like to move one DIV element inside another. For example, I want to move this (including all children): <div id="source"> ... </div> into this: <div id="destination"> ... </div> so that I have this: <div id="destination"> <div id="source"> ... </div> </div>
<p>I would like to move one DIV element inside another. For example, I want to move this (including all children):</p> <pre class="lang-html prettyprint-override"><code>&lt;div id=&quot;source&quot;&gt; ... &lt;/div&gt; </code></pre> <p>into this:</p> <pre class="lang-html prettyprint-override"><code>&lt;div id=&quot...
[ { "answerId": 1279963, "score": 1955, "isAccepted": true, "createdAt": "2009-08-14T20:16:45", "ownerDisplayName": "Andrew Hare", "ownerUserId": 34211, "bodyText": "You may want to use the appendTo function (which adds to the end of the element): $(\"#source\").appendTo(\"#destination\");...
1
1646698
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1646698/what-is-the-new-keyword-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,646,698
What is the 'new' keyword in JavaScript?
1,931
386,461
18
true
true
[ "javascript", "new-operator" ]
2009-10-29T21:32:45
2024-07-23T22:14:49
Alon Gubkin
false
CC BY-SA 3.0
3,658,673
140,937
57,251
null
null
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null
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The new keyword in JavaScript can be quite confusing when it is first encountered, as people tend to think that JavaScript is not an object-oriented programming language. What is it? What problems does it solve? When is it appropriate and when not?
<p>The <code>new</code> keyword in JavaScript can be quite confusing when it is first encountered, as people tend to think that JavaScript is not an object-oriented programming language.</p> <ul> <li>What is it?</li> <li>What problems does it solve?</li> <li>When is it appropriate and when not?</li> </ul>
[ { "answerId": 3658673, "score": 2304, "isAccepted": true, "createdAt": "2010-09-07T12:30:58", "ownerDisplayName": "Daniel Howard", "ownerUserId": 441426, "bodyText": "It does 5 things: It creates a new object. The type of this object is simply object . It sets this new object's internal,...
1
20279484
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/20279484/how-to-access-the-correct-this-inside-a-callback
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
20,279,484
How to access the correct `this` inside a callback
1,924
659,142
16
true
true
[ "javascript", "callback", "this" ]
2013-11-29T06:13:11
2025-10-22T20:14:45
Felix Kling
false
CC BY-SA 4.0
20,279,485
218,196
821,265
null
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I have a constructor function which registers an event handler: function MyConstructor(data, transport) { this.data = data; transport.on('data', function () { alert(this.data); }); } // Mock transport object var transport = { on: function(event, callback) { setTimeout(callback, 1000); } }; // called as var obj = new My...
<p>I have a constructor function which registers an event handler:</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="false" data-babel="false"> <div class="snippet-code"> <pre class="snippet-code-js lang-js prettyprint-override"><code>function MyConstructor(data, transport) { this.data = ...
[ { "answerId": 20279485, "score": 2315, "isAccepted": true, "createdAt": "2013-11-29T06:13:11", "ownerDisplayName": "Felix Kling", "ownerUserId": 218196, "bodyText": "What you should know about this this (aka \"the context\") is a special keyword inside each function and its value only de...
1
9899372
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/9899372/vanilla-javascript-equivalent-of-jquerys-ready-how-to-call-a-function-whe
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
9,899,372
Vanilla JavaScript equivalent of jQuery's $.ready() - how to call a function when the page/DOM is ready for it
1,921
2,374,049
10
true
true
[ "javascript", "jquery", "html" ]
2012-03-27T23:57:21
2022-06-29T20:23:23
chris
true
null
9,899,701
768,392
37,065
null
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With jQuery, we all know the wonderful .ready() function: $('document').ready(function(){}); However, let's say I want to run a function that is written in standard JavaScript with no library backing it, and that I want to launch a function as soon as the page is ready to handle it. What's the proper way to approach th...
<p>With jQuery, we all know the wonderful <code>.ready()</code> function:</p> <pre><code>$('document').ready(function(){}); </code></pre> <p>However, let's say I want to run a function that is written in standard JavaScript with no library backing it, and that I want to launch a function as soon as the page is ready ...
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1
135448
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/135448/how-do-i-check-if-an-object-has-a-specific-property-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
135,448
How do I check if an object has a specific property in JavaScript?
1,910
1,505,995
33
true
true
[ "javascript" ]
2008-09-25T19:27:06
2024-08-18T04:44:04
sheats
false
CC BY-SA 4.0
136,411
4,915
35,022
null
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How do I check if an object has a specific property in JavaScript? Consider: x = {'key': 1}; if ( x.hasOwnProperty('key') ) { //Do this } Is there another way to do it?
<p>How do I check if an object has a specific property in JavaScript?</p> <p>Consider:</p> <pre><code>x = {'key': 1}; if ( x.hasOwnProperty('key') ) { //Do this } </code></pre> <p>Is there another way to do it?</p>
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1
18641899
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/18641899/what-is-the-difference-between-bower-and-npm
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
18,641,899
What is the difference between Bower and npm?
1,909
339,938
9
true
true
[ "javascript", "npm", "bower", "dependency-management" ]
2013-09-05T16:53:19
2025-01-12T16:15:34
Nafiul Islam
false
CC BY-SA 4.0
18,652,918
1,624,921
82,976
null
null
null
null
null
null
null
null
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null
null
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null
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What is the fundamental difference between bower and npm ? Just want something plain and simple. I've seen some of my colleagues use bower and npm interchangeably in their projects.
<p>What is the fundamental difference between <code>bower</code> and <code>npm</code>? Just want something plain and simple. I've seen some of my colleagues use <code>bower</code> and <code>npm</code> interchangeably in their projects.</p>
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1
3455405
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/3455405/how-do-i-remove-a-key-from-a-javascript-object
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
3,455,405
How do I remove a key from a JavaScript object?
1,905
2,130,542
3
true
true
[ "javascript" ]
2010-08-11T04:59:03
2022-08-05T15:14:45
Martin Ongtangco
true
null
3,455,416
162,381
23,625
null
null
null
null
null
null
null
null
null
null
null
null
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null
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Let's say we have an object with this format: var thisIsObject= { 'Cow' : 'Moo', 'Cat' : 'Meow', 'Dog' : 'Bark' }; I wanted to do a function that removes by key: removeFromObjectByKey('Cow');
<p>Let's say we have an object with this format:</p> <pre><code>var thisIsObject= { 'Cow' : 'Moo', 'Cat' : 'Meow', 'Dog' : 'Bark' }; </code></pre> <p>I wanted to do a function that removes by key:</p> <pre><code>removeFromObjectByKey('Cow'); </code></pre>
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1
7202157
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/7202157/why-does-return-the-string-10
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
7,202,157
Why does ++[[]][+[]]+[+[]] return the string "10"?
1,896
238,255
10
true
true
[ "javascript", "syntax", "jsfuck" ]
2011-08-26T08:46:14
2024-01-29T15:25:02
JohnJohnGa
false
CC BY-SA 4.0
7,202,287
324,853
15,715
null
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null
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This is valid and returns the string "10" in JavaScript ( more examples here ): console.log(++[[]][+[]]+[+[]]) Why? What is happening here?
<p>This is valid and returns the string <code>"10"</code> in JavaScript (<a href="http://sla.ckers.org/forum/read.php?24,33349,33405" rel="noreferrer">more examples here</a>):</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false"> <div class="snippet-code"> <pre class="s...
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1
14810506
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/14810506/map-function-for-objects-instead-of-arrays
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
14,810,506
'map' function for objects (instead of arrays)
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2,995,108
40
true
true
[ "javascript", "node.js", "functional-programming", "map-function" ]
2013-02-11T10:41:12
2025-08-05T18:36:18
Randomblue
false
CC BY-SA 4.0
14,810,722
707,381
117,223
null
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I have an object: myObject = { 'a': 1, 'b': 2, 'c': 3 } I am looking for a native method, similar to Array.prototype.map that would be used as follows: newObject = myObject.map(function (value, label) { return value * value; }); // newObject is now { 'a': 1, 'b': 4, 'c': 9 } Does JavaScript have such a map function for...
<p>I have an object:</p> <pre><code>myObject = { 'a': 1, 'b': 2, 'c': 3 } </code></pre> <p>I am looking for a native method, similar to <code>Array.prototype.map</code> that would be used as follows:</p> <pre><code>newObject = myObject.map(function (value, label) { return value * value; }); // newObject is now ...
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1
921789
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/921789/how-to-loop-through-a-plain-javascript-object-with-the-objects-as-members
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
921,789
How to loop through a plain JavaScript object with the objects as members
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2,135,521
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true
true
[ "javascript", "loops" ]
2009-05-28T16:18:14
2023-12-15T03:26:59
edt
false
CC BY-SA 4.0
921,808
32,242
22,490
null
null
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null
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How can I loop through all members in a JavaScript object, including values that are objects? For example, how could I loop through this (accessing the "your_name" and "your_message" for each)? var validation_messages = { "key_1": { "your_name": "jimmy", "your_msg": "hello world" }, "key_2": { "your_name": "billy", "yo...
<p>How can I loop through all members in a JavaScript object, including values that are objects?</p> <p>For example, how could I loop through this (accessing the &quot;your_name&quot; and &quot;your_message&quot; for each)?</p> <pre><code>var validation_messages = { &quot;key_1&quot;: { &quot;your_name&quot...
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1
646628
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/646628/how-to-check-if-a-string-startswith-another-string
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
646,628
How to check if a string "StartsWith" another string?
1,826
1,076,974
19
true
true
[ "javascript", "string", "startswith" ]
2009-03-14T20:12:51
2023-12-12T19:03:35
sol
false
CC BY-SA 4.0
646,643
null
null
null
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How would I write the equivalent of C#'s String.StartsWith in JavaScript? var haystack = 'hello world'; var needle = 'he'; haystack.startsWith(needle) == true Note: This is an old question, and as pointed out in the comments ECMAScript 2015 (ES6) introduced the .startsWith method. However, at the time of writing this u...
<p>How would I write the equivalent of C#'s <a href="http://msdn.microsoft.com/en-us/library/baketfxw.aspx" rel="noreferrer"><code>String.StartsWith</code></a> in JavaScript?</p> <pre><code>var haystack = 'hello world'; var needle = 'he'; haystack.startsWith(needle) == true </code></pre> <p>Note: This is an old ques...
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1
313893
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/313893/how-to-measure-time-taken-by-a-function-to-execute
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
313,893
How to measure time taken by a function to execute
1,820
1,240,082
30
true
true
[ "javascript", "profiling" ]
2008-11-24T11:09:14
2025-01-22T06:32:34
Julius A
false
CC BY-SA 4.0
1,975,103
13,370
40,082
null
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I need to get execution time in milliseconds. Note : I originally asked this question back in 2008. The accepted answer then was to use new Date().getTime() However, we can all agree now that using the standard performance.now() API is more appropriate. I am therefore changing the accepted answer to this one.
<p>I need to get execution time in milliseconds.</p> <p><strong>Note</strong>: I originally asked this question back in 2008. The accepted answer then was to use <a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTime" rel="noreferrer"><code>new Date().getTime()</code></a>...
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1
1291942
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1291942/what-does-javascriptvoid0-mean
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,291,942
What does "javascript:void(0)" mean?
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2,883,608
14
true
true
[ "javascript", "void" ]
2009-08-18T05:20:13
2024-07-28T13:57:20
omg
false
CC BY-SA 4.0
1,291,950
104,015
141,112
null
null
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<a href="javascript:void(0)" id="loginlink">login</a> I've seen such href s many times, but I don't know what exactly that means.
<pre class="lang-html prettyprint-override"><code>&lt;a href=&quot;javascript:void(0)&quot; id=&quot;loginlink&quot;&gt;login&lt;/a&gt; </code></pre> <p>I've seen such <code>href</code>s many times, but I don't know what exactly that means.</p>
null
0
109086
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/109086/stop-setinterval-call-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
109,086
Stop setInterval call in JavaScript
1,802
1,522,385
9
true
true
[ "javascript", "dom-events", "setinterval" ]
2008-09-20T19:29:55
2023-05-13T13:21:56
cnu
false
CC BY-SA 4.0
109,091
1,448
37,385
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null
null
I am using setInterval(fname, 10000); to call a function every 10 seconds in JavaScript. Is it possible to stop calling it on some event? I want the user to be able to stop the repeated refresh of data.
<p>I am using <code>setInterval(fname, 10000);</code> to call a function every 10 seconds in JavaScript. Is it possible to stop calling it on some event? </p> <p>I want the user to be able to stop the repeated refresh of data.</p>
[ { "answerId": 109091, "score": 2774, "isAccepted": true, "createdAt": "2008-09-20T19:30:59", "ownerDisplayName": "John Millikin", "ownerUserId": 3560, "bodyText": "setInterval() returns an interval ID, which you can pass to clearInterval() : var refreshIntervalId = setInterval(fname, 100...
1
11177954
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/11177954/how-do-i-completely-uninstall-node-js-and-reinstall-from-beginning-mac-os-x
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
11,177,954
How do I completely uninstall Node.js, and reinstall from beginning (Mac OS X)
1,798
3,103,063
35
true
true
[ "javascript", "node.js", "npm" ]
2012-06-24T13:40:56
2026-02-06T09:31:54
Dominic Tancredi
false
CC BY-SA 4.0
11,178,106
1,247,659
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My version of node is always v0.6.1-pre even after I install brew node and NVM install v0.6.19. My node version is: node -v v0.6.1-pre NVM says this (after I install a version of node for the first time in one bash terminal): nvm ls v0.6.19 current: v0.6.19 But when I restart bash, this is what I see: nvm ls v0.6.19 cu...
<p>My version of node is always v0.6.1-pre even after I install brew node and NVM install v0.6.19.</p> <p>My node version is:</p> <pre class="lang-none prettyprint-override"><code>node -v v0.6.1-pre </code></pre> <p>NVM says this (after I install a version of node for the first time in one bash terminal):</p> <pr...
[ { "answerId": 11178106, "score": 2031, "isAccepted": true, "createdAt": "2012-06-24T14:04:58", "ownerDisplayName": "Dominic Tancredi", "ownerUserId": 1247659, "bodyText": "Apparently, there was a /Users/myusername/local folder that contained a include with node and lib with node and node...
1
21692646
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/21692646/how-does-facebook-disable-the-browsers-integrated-developer-tools
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
21,692,646
How does Facebook disable the browser's integrated Developer Tools?
1,791
315,455
14
true
true
[ "javascript", "facebook", "google-chrome-devtools" ]
2014-02-11T03:42:08
2024-06-27T22:07:54
Derek 朕會功夫
false
CC BY-SA 4.0
21,693,931
283,863
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So apparently because of the recent scams, the developer tools are exploited by people to post spam and even used to "hack" accounts. Facebook has blocked the developer tools, and I can't even use the console. How did they do that?? One Stack Overflow post claimed it is impossible , but Facebook has proven them wrong. ...
<p>So apparently because of the recent scams, the developer tools are exploited by people to post spam and even used to &quot;hack&quot; accounts. Facebook has blocked the developer tools, and I can't even use the console.</p> <p><img src="https://i.sstatic.net/Wiatp.png" alt="Enter image description here" /></p> <p>Ho...
[ { "answerId": 21693931, "score": 2540, "isAccepted": true, "createdAt": "2014-02-11T05:33:16", "ownerDisplayName": "Alf", "ownerUserId": 630946, "bodyText": "I'm a security engineer at Facebook and this is my fault. We're testing this for some users to see if it can slow down some attack...
1
1184624
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1184624/convert-form-data-to-javascript-object-with-jquery
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,184,624
Convert form data to JavaScript object with jQuery
1,771
1,112,708
58
true
true
[ "javascript", "jquery", "json", "serialization" ]
2009-07-26T13:39:54
2025-02-26T20:13:04
Yisroel
false
CC BY-SA 4.0
1,186,309
35,091
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How do I convert all elements of my form to a JavaScript object? I'd like to have some way of automatically building a JavaScript object from my form, without having to loop over each element. I do not want a string, as returned by $('#formid').serialize(); , nor do I want the map returned by $('#formid').serializeArra...
<p>How do I convert all elements of my form to a JavaScript object? </p> <p>I'd like to have some way of automatically building a JavaScript object from my form, without having to loop over each element. I do not want a string, as returned by <code>$('#formid').serialize();</code>, nor do I want the map returned by <c...
[ { "answerId": 1186309, "score": 1741, "isAccepted": true, "createdAt": "2009-07-27T03:38:41", "ownerDisplayName": "Tobias Cohen", "ownerUserId": 66617, "bodyText": "serializeArray already does exactly that. You just need to massage the data into your required format: function objectifyFo...
1
133925
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/133925/javascript-post-request-like-a-form-submit
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
133,925
JavaScript post request like a form submit
1,767
1,894,366
32
true
true
[ "javascript", "forms", "post", "submit" ]
2008-09-25T15:15:43
2024-06-12T14:27:44
Joseph Holsten
false
CC BY-SA 4.0
133,997
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I'm trying to direct a browser to a different page. If I wanted a GET request, I might say document.location.href = 'http://example.com/q=a'; But the resource I'm trying to access won't respond properly unless I use a POST request. If this were not dynamically generated, I might use the HTML <form action="http://exampl...
<p>I'm trying to direct a browser to a different page. If I wanted a GET request, I might say</p> <pre class="lang-js prettyprint-override"><code>document.location.href = 'http://example.com/q=a'; </code></pre> <p>But the resource I'm trying to access won't respond properly unless I use a POST request. If this were not...
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1
4935632
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/4935632/parse-json-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
4,935,632
Parse JSON in JavaScript?
1,763
2,026,928
16
true
true
[ "javascript", "json", "parsing" ]
2011-02-08T16:34:03
2020-12-18T13:50:33
user605334
true
null
4,935,684
null
null
null
null
null
null
null
null
null
null
null
null
null
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null
null
null
I want to parse a JSON string in JavaScript. The response is something like var response = '{"result":true,"count":1}'; How can I get the values result and count from this?
<p>I want to parse a JSON string in JavaScript. The response is something like</p> <pre><code>var response = '{"result":true,"count":1}'; </code></pre> <p>How can I get the values <code>result</code> and <code>count</code> from this?</p>
[ { "answerId": 4935684, "score": 2044, "isAccepted": true, "createdAt": "2011-02-08T16:38:35", "ownerDisplayName": "Andy E", "ownerUserId": 94197, "bodyText": "The standard way to parse JSON in JavaScript is JSON.parse() The JSON API was introduced with ES5 (2011) and has since been imple...
1
432493
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/432493/how-do-you-access-the-matched-groups-in-a-javascript-regular-expression
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
432,493
How do you access the matched groups in a JavaScript regular expression?
1,763
1,138,745
24
true
true
[ "javascript", "regex" ]
2009-01-11T07:21:20
2025-02-20T12:02:39
nickf
false
CC BY-SA 4.0
432,503
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I want to match a portion of a string using a regular expression and then access that parenthesized substring: var myString = "something format_abc"; // I want "abc" var arr = /(?:^|\s)format_(.*?)(?:\s|$)/.exec(myString); console.log(arr); // Prints: [" format_abc", "abc"] .. so far so good. console.log(arr[1]); // Pr...
<p>I want to match a portion of a string using a <a href="https://en.wikipedia.org/wiki/Regular_expression" rel="noreferrer">regular expression</a> and then access that parenthesized substring:</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false"> <div class="snippet-code...
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1
3895478
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/3895478/does-javascript-have-a-method-like-range-to-generate-a-range-within-the-supp
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
3,895,478
Does JavaScript have a method like "range()" to generate a range within the supplied bounds?
1,759
1,723,618
92
true
true
[ "javascript", "arrays", "functional-programming" ]
2010-10-09T02:37:29
2024-10-20T10:21:31
alex
false
CC BY-SA 4.0
3,895,521
31,671
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In PHP, you can do... range(1, 3); // Array(1, 2, 3) range("A", "C"); // Array("A", "B", "C") That is, there is a function that lets you get a range of numbers or characters by passing the upper and lower bounds. Is there anything built-in to JavaScript natively for this? If not, how would I implement it?
<p>In PHP, you can do...</p> <pre><code>range(1, 3); // Array(1, 2, 3) range("A", "C"); // Array("A", "B", "C") </code></pre> <p>That is, there is a function that lets you get a range of numbers or characters by passing the upper and lower bounds.</p> <p>Is there anything built-in to JavaScript natively for this? If...
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1
979975
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/979975/get-the-values-from-the-get-parameters-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
979,975
Get the values from the "GET" parameters (JavaScript)
1,756
2,912,456
63
true
true
[ "javascript", "url", "url-parameters" ]
2009-06-11T08:32:49
2022-08-05T08:02:43
joe
true
null
979,995
120,457
35,257
null
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I have a URL with some GET parameters as follows: www.test.com/t.html?a=1&b=3&c=m2-m3-m4-m5 I need to get the whole value of c . I tried to read the URL, but I got only m2 . How do I do this using JavaScript?
<p>I have a URL with some GET parameters as follows:</p> <pre><code>www.test.com/t.html?a=1&amp;b=3&amp;c=m2-m3-m4-m5 </code></pre> <p>I need to get the whole value of <code>c</code>. I tried to read the URL, but I got only <code>m2</code>. How do I do this using JavaScript?</p>
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1
507138
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/507138/how-to-add-a-class-to-an-html-element-with-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
507,138
How to add a class to an HTML element with JavaScript?
1,753
2,835,748
28
true
true
[ "javascript", "html", "dom-manipulation" ]
2009-02-03T13:54:00
2026-02-24T06:03:31
Blankman
false
CC BY-SA 4.0
507,157
39,677
268,914
null
null
null
null
null
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I have an element that already has a class: <div class="someclass"> ... </div> How can i add a class to the div (not replace, but add) with JavaScript?
<p>I have an element that already has a class:</p> <pre class="lang-html prettyprint-override"><code>&lt;div class=&quot;someclass&quot;&gt; ... &lt;/div&gt; </code></pre> <p>How can i add a class to the <code>div</code> (not replace, but add) with JavaScript?</p>
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2
5076944
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/5076944/what-is-the-difference-between-null-and-undefined-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
5,076,944
What is the difference between null and undefined in JavaScript?
1,752
765,647
39
true
true
[ "javascript", "null", "undefined" ]
2011-02-22T10:30:10
2024-07-05T22:31:05
user605334
false
CC BY-SA 4.0
5,076,962
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
What is the difference between null and undefined in JavaScript?
<p>What is the difference between <code>null</code> and <code>undefined</code> in JavaScript?</p>
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1
11508463
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/11508463/javascript-set-object-key-by-variable
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
11,508,463
JavaScript set object key by variable
1,748
1,486,840
9
true
true
[ "javascript" ]
2012-07-16T16:24:23
2026-04-09T00:53:22
Hunter McMillen
true
null
11,508,490
702,638
61,834
null
null
null
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null
null
null
null
null
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I am building some objects in JavaScript and pushing those objects into an array, I am storing the key I want to use in a variable then creating my objects like so: var key = "happyCount"; myArray.push( { key : someValueArray } ); but when I try to examine my array of objects for every object the key is "key" instead o...
<p>I am building some objects in JavaScript and pushing those objects into an array, I am storing the key I want to use in a variable then creating my objects like so:</p> <pre><code>var key = "happyCount"; myArray.push( { key : someValueArray } ); </code></pre> <p>but when I try to examine my array of objects for ev...
[ { "answerId": 11508490, "score": 3089, "isAccepted": true, "createdAt": "2012-07-16T16:26:12", "ownerDisplayName": "gen_Eric", "ownerUserId": 206403, "bodyText": "You need to make the object first, then use [] to set it. var key = \"happyCount\"; var obj = {}; obj[key] = someValueArray; ...
1
13789618
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/13789618/differences-between-lodash-and-underscore-js
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
13,789,618
Differences between Lodash and Underscore.js
1,729
373,953
12
true
true
[ "underscore.js", "javascript", "lodash" ]
2012-12-09T17:08:36
2022-10-14T19:08:01
Brian M. Hunt
true
null
13,898,916
19,212
84,602
null
null
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null
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Why would someone prefer either the Lodash or Underscore.js utility library over the other? Lodash seems to be a drop-in replacement for underscore, the latter having been around longer. I think both are brilliant, but I do not know enough about how they work to make an educated comparison, and I would like to know mor...
<p>Why would someone prefer either the <a href="http://lodash.com/" rel="noreferrer">Lodash</a> or <a href="http://underscorejs.org/" rel="noreferrer">Underscore.js</a> utility library over the other?</p> <p>Lodash seems to be a drop-in replacement for underscore, the latter having been around longer.</p> <p>I think bo...
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1
979256
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/979256/sorting-an-array-of-objects-by-property-values
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
979,256
Sorting an array of objects by property values
1,727
1,639,463
27
true
true
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2009-06-11T03:59:54
2025-01-03T06:24:26
TomHankers
false
CC BY-SA 4.0
979,289
null
null
null
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I've got the following objects using AJAX and stored them in an array: var homes = [ { "h_id": "3", "city": "Dallas", "state": "TX", "zip": "75201", "price": "162500" }, { "h_id": "4", "city": "Bevery Hills", "state": "CA", "zip": "90210", "price": "319250" }, { "h_id": "5", "city": "New York", "state": "NY", "zip": "0...
<p>I've got the following objects using AJAX and stored them in an array:</p> <pre><code>var homes = [ { "h_id": "3", "city": "Dallas", "state": "TX", "zip": "75201", "price": "162500" }, { "h_id": "4", "city": "Bevery Hills", "state": "CA", ...
[ { "answerId": 979289, "score": 2232, "isAccepted": true, "createdAt": "2009-06-11T04:12:35", "ownerDisplayName": "Stobor", "ownerUserId": 43452, "bodyText": "Sort homes by price in ascending order: homes.sort(function(a, b) { return parseFloat(a.price) - parseFloat(b.price); }); Or after...
1
1911015
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/1911015/how-do-i-debug-node-js-applications
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
1,911,015
How do I debug Node.js applications?
1,715
568,328
42
true
true
[ "javascript", "node.js", "debugging", "google-chrome-devtools" ]
2009-12-15T22:50:07
2023-06-25T18:29:01
Fabian Jakobs
false
CC BY-SA 3.0
2,536,734
129,322
29,183
null
null
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null
null
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How do I debug a Node.js server application? Right now I'm mostly using alert debugging with print statements like this: sys.puts(sys.inspect(someVariable)); There must be a better way to debug. I know that Google Chrome has a command-line debugger. Is this debugger available for Node.js as well?
<p>How do I debug a Node.js server application?</p> <p>Right now I'm mostly using <em>alert debugging</em> with print statements like this:</p> <pre><code>sys.puts(sys.inspect(someVariable)); </code></pre> <p>There must be a better way to debug. I know that <a href="http://en.wikipedia.org/wiki/Google_Chrome" rel="n...
null
0
523643
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/523643/difference-between-and-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
523,643
Difference between == and === in JavaScript
1,711
1,054,703
2
true
true
[ "javascript", "comparison-operators", "equality-operator", "identity-operator" ]
2009-02-07T11:53:04
2025-06-24T21:28:52
Shiva
true
null
523,647
51,570
18,293
null
null
null
null
null
null
null
null
null
null
null
null
null
null
null
What is the difference between == and === in JavaScript? I have also seen != and !== operators. Are there more such operators?
<p>What is the difference between <code>==</code> and <code>===</code> in JavaScript? I have also seen <code>!=</code> and <code>!==</code> operators. Are there more such operators?</p>
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1
14667713
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/14667713/how-to-convert-a-string-to-number-in-typescript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
14,667,713
How to convert a string to number in TypeScript?
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2,808,282
22
true
true
[ "javascript", "typescript" ]
2013-02-02T23:34:18
2025-09-26T09:44:15
Paul0515
false
CC BY-SA 4.0
14,668,510
1,627,079
25,745
null
null
null
null
null
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null
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null
null
null
Given a string representation of a number, how can I convert it to number type in TypeScript? var numberString: string = "1234"; var numberValue: number = /* what should I do with `numberString`? */;
<p>Given a string representation of a number, how can I convert it to <code>number</code> type in TypeScript?</p> <pre><code>var numberString: string = "1234"; var numberValue: number = /* what should I do with `numberString`? */; </code></pre>
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2
847185
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/847185/convert-a-unix-timestamp-to-time-in-javascript
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
847,185
Convert a Unix timestamp to time in JavaScript
1,690
2,705,730
35
true
true
[ "javascript", "date", "time", "time-format" ]
2009-05-11T08:23:28
2024-02-05T12:13:20
roflwaffle
false
CC BY-SA 4.0
847,196
49,887
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I am storing time in a MySQL database as a Unix timestamp and that gets sent to some JavaScript code. How would I get just the time out of it? For example, in HH/MM/SS format.
<p>I am storing time in a MySQL database as a Unix timestamp and that gets sent to some JavaScript code. How would I get just the time out of it?</p> <p>For example, in <code>HH/MM/SS</code> format.</p>
[ { "answerId": 847196, "score": 2367, "isAccepted": true, "createdAt": "2009-05-11T08:28:50", "ownerDisplayName": "Aron Rotteveel", "ownerUserId": 11568, "bodyText": "let unix_timestamp = 1549312452; // Create a new JavaScript Date object based on the timestamp // multiplied by 1000 so th...
1
497094
question
stackoverflow
2026-08-03T01:37:30
null
null
null
null
null
https://stackoverflow.com/questions/497094/how-do-i-find-out-which-dom-element-has-the-focus
gRfaNe5dFEERAlPiJ
OOGxFG8S0YK0PA8Ta
497,094
How do I find out which DOM element has the focus?
1,690
990,992
22
true
true
[ "javascript", "dom" ]
2009-01-30T20:21:31
2024-10-15T00:42:53
Tony Peterson
false
CC BY-SA 4.0
497,108
26,140
21,364
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I would like to find out, in JavaScript, which element currently has focus. I've been looking through the DOM and haven't found what I need, yet. Is there a way to do this, and how? The reason I was looking for this: I'm trying to make keys like the arrows and enter navigate through a table of input elements. Tab works...
<p>I would like to find out, in JavaScript, which element currently has focus. I've been looking through the DOM and haven't found what I need, yet. Is there a way to do this, and how?</p> <p>The reason I was looking for this:</p> <p>I'm trying to make keys like the arrows and <code>enter</code> navigate through a ta...
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1