JavaScript Pocket Reference, 2nd Edition

Name

Array

Constructor

new Array( )             // empty
new Array(n)            // n undefined elements
new Array(e0, e1,...)   // specified elements

Literal Syntax

In JavaScript 1.2, JScript 3.0, and ECMA v3, you can create and initialize an array by placing a comma-separated list of expressions within square brackets. The values of these expressions become the elements of the array. For example:

var a = [1, true, 'abc'];
var b = [a[0], a[0]*2, f(x)];

Properties

length

A read/write integer specifying the number of elements in the array, or, when the array does not have contiguous elements, a number one larger than the index of the last element in the array. Changing the value of this property truncates or extends the array.

Methods

concat(value, ...)

Returns a new array, which is formed by concatenating each of the specified arguments to this one. If any arguments to concat( ) are themselves arrays, their elements are concatenated, rather than the arrays themselves. JS 1.2; JScript 3.0; ECMA v3.

join(separator)

Returns the string that results from converting each element of an array to a string and then concatenating the strings together, with the separator string between elements.

pop( )

Removes and returns the last element of the array, decrementing the array length. JS 1.2; JScript 5.5; ECMA v3.

push(value, ...)

Appends the specified value or values to the end of the array, and returns the new length of the array. JS 1.2; JScript 5.5; ECMA v3.

reverse( )

Reverses the order of the elements of an array. Returns nothing. ...