Java Script
JavaScript (not to be confused with Java) is a high-level, dynamic, multi-paradigm, weakly-typed language used for both client-side and server-side scripting. Its primary use is in rendering and allowing manipulation of web pages. Use this tag for questions regarding ECMAScript and its various dialects/implementations (excluding ActionScript and Google-Apps-Script).
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Checking if a key exists in a JavaScript object?
How do I check if a particular key exists in a JavaScript object or array? If a key doesn't exist, and I
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How to insert an item into an array at a specific index (JavaScript)
I am looking for a JavaScript array insert method, in the style of: arr.insert(index, item) Preferably in jQu
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Loop through an array in JavaScript
In Java you can use a for loop to traverse objects in an array as follows: String[] myStringArray = {"Hello",
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What is the !! (not not) operator in JavaScript?
I saw some code that seems to use an operator I don't recognize, in the form of two exclamation points, l
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How do I copy to the clipboard in JavaScript?
What is the best way to copy text to the clipboard (multi-browser)? I have tried: function copyToClipboard(tex
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How do I test for an empty JavaScript object?
After an AJAX request, sometimes my application may return an empty object, like: var a = {}; How can I che
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Which "href" value should I use for JavaScript links, "#" or "javascript:void(0)"?
The following are two methods of building a link that has the sole purpose of running JavaScript code. Which i
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Why does Google prepend while(1); to their JSON responses?
Why does Google prepend while(1); to their (private) JSON responses? For example, here's a response whil
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How do I make the first letter of a string uppercase in JavaScript?
How do I make the first letter of a string uppercase, but not change the case of any of the other letters? For
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Setting "checked" for a checkbox with jQuery
I'd like to do something like this to tick a checkbox using jQuery: $(".myCheckBox").checked(true); or
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How do you get a timestamp in JavaScript?
Something similar to Unix's timestamp, that is a single number that represents the current time and date.
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How do I check if an array includes a value in JavaScript?
What is the most concise and efficient way to find out if a JavaScript array contains a value? This is the onl
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How to create a GUID / UUID
I'm trying to create globally-unique identifiers in JavaScript. I'm not sure what routines are avai
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How do I check whether a checkbox is checked in jQuery?
I need to check the checked property of a checkbox and perform an action based on the checked property using j
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How to replace all occurrences of a string in JavaScript
I have this string in my JavaScript code: "Test abc test test abc test test test abc test test abc" Doing: st
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How to validate an email address in JavaScript
Is there a regular expression to verify an email address in JavaScript?
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For-each over an array in JavaScript
How can I loop through all the entries in an array using JavaScript? I thought it was something like this: f
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What's the difference between using "let" and "var"?
ECMAScript 6 introduced the let statement. I've heard that it's described as a local variable, but I
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