ActionScript for Flash MX: The Definitive Guide, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

Adding Elements to an Array

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// Create an array with three elements

var myColors = ["green", "red", "blue"];

// Add 47 empty elements, numbered 3 through 49, to the array

myColors.length = 50;

You can use this approach to create a number of empty elements to hold some data

you expect to accumulate, such as student test scores.

Adding New Elements with Array Methods

We can use built-in array methods to handle more complex array operations. (In

Chapter 12 you’ll learn that a method is a function that operates on an object.)

The push() method

The push() method appends one or more elements to the end of an array. It automat-

ically appends the data after the last numbered element of the array, so we don’t

need to worry about how many elements already exist. The push() method can also

append multiple elements to an array at once. To invoke push() on an array, we use

the array name, followed by the dot operator, the keyword push, and zero or more

items in parentheses:

arrayName.push(item1, item2,...itemn);

where item1, item2, ...itemn is a comma-separated list of items to be appended to the

end of the array as new elements. Here are some examples:

// Create an array with two elements

var menuItems = ["home", "quit"];

// Add an element

// menuItems becomes ["home", "quit", "products"]

menuItems.push("products"); ...