JavaScript Core Reference - Beginning JavaScript - page 680

Array
The Array object represents an array of variables. It was introduced in JavaScript 1.1. An Array object
can be created with the Array constructor.

var objArray = new Array(10) // an array of 11 elements
var objArray = new Array(“1”, “2”, “4”) // an array of 3 elements

Arrays can also be created using array literal syntax.

var objArray = [];

Literal syntax is the preferred method of creating an array.

Properties
Property Introduced Description

constructor JavaScript 1.1 Used to reference the constructor function for

the object.

length JavaScript 1.1 Returns the number of elements in the array.

prototype JavaScript 1.1 Returns the prototype for the object, which

can be used to extend the object's interface.

Methods
Square brackets ( [] ) surrounding a parameter means that parameter is optional.

Method Introduced Description

concat(value1 [, value2,…]) JavaScript 1.2 Concatenates two arrays and returns

the new array thus formed.

every(testFn(element, index,
array))

JavaScript 1.6 Iterates over the array, executing

testFn() on every element. Returns
true if all iterations return true .
Otherwise, it returns false .

filter(testFn(element, index,
array))

JavaScript 1.6 Iterates over the array, executing

testFn() on every element. Returns
a new array of elements that pass
testFn().

foreach(fn(element, index,
array))

JavaScript 1.6 Iterates over the array, executing fn()

on every element.

indexOf(element
[, startIndex])

JavaScript 1.6 Returns an index of the specifi ed

element if found, or -1 if not found.
Starts at startIndex if specifi ed.