Add new value to an existing array in JavaScript [duplicate]

Question

In PHP, I'd do something like:

$array = array(); $array[] = "value1"; $array[] = "value2"; $array[] = "value3"; 

How would I do the same thing in JavaScript?

Answer 1

You don't need jQuery for that. Use regular javascript

var arr = new Array(); // or var arr = []; arr.push('value1'); arr.push('value2'); 

Note: In javascript, you can also use Objects as Arrays, but still have access to the Array prototypes. This makes the object behave like an array:

var obj = new Object(); Array.prototype.push.call(obj, 'value'); 

will create an object that looks like:

{     0: 'value',     length: 1 } 

You can access the vaules just like a normal array f.ex obj[0].

Answer 2

This has nothing to do with jQuery, just JavaScript in general.

To create an array in JavaScript:

var a = []; 

Or:

var a = ['value1', 'value2', 'value3']; 

To append values on the end of existing array:

a.push('value4'); 

To create a new array, you should really use [] instead of new Array() for the following reasons:

• new Array(1, 2) is equivalent to [1, 2], but new Array(1) is not equivalent to [1]. Rather the latter is closer to [undefined], since a single integer argument to the Array constructor indicates the desired array length.
• Array, just like any other built-in JavaScript class, is not a keyword. Therefore, someone could easily define Array in your code to do something other than construct an array.