Arrays
Arrays allow you to group multiple values (called members) in a single variable. Standard array values are numerically indexed beginning with 0 and counting upward. They can be declared in a few different ways as well:
var array_1 = new Array( ); // empty array var array_2 = new Array(2); // array with two undefined members var array_3 = []; // shorthand empty array
As with scalars, an array’s values can be set when it is declared:
var cats = new Array( 'Sabine', 'Dakota' ); var names = [ 'Aaron', 'Kelly' ];
or the values can be assigned afterward:
var cats = new Array( ); cats[0] = 'Sabine'; cats[1] = 'Dakota';
An array can contain any sort of data in its members:
var sabine = [ 'cat', 'female', 9, true ]; // Sabine is a 9-year-old female cat that is spayed
even other arrays :
var cats = new Array( 2 ); cats[0] = [ 'Sabine', 'cat', 'female', 9, true ]; cats[1] = [ 'Dakota', 'cat', 'male', 8, true ];
An array member can also have its value assigned by a variable:
var cats = new Array( 2 ); var sabine = [ 'cat', 'female', 9, true ]; var dakota = [ 'cat', 'male', 8, true ]; cats[0] = sabine; cats[1] = dakota;
Associative arrays are a specialized form of array (sometimes referred to as a “hash”) that use keywords as their indexes. The following example uses a few different forms of arrays and scalars:
var cats = new Array( 2 ); cats['sabine'] = [ 'cat', 'female', 9, true ]; cats['dakota'] = [ 'cat', 'male', 8, true ]; var reps = []; reps['sheldon'] = [ 'tortoise', 'male', 5, false ...
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