MACROMEDIA FLASH MX, Справочник

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104 Chapter 2: ActionScript Language Reference
Constructor for the Array class
Availability
Flash Player 5.
Usage
new Array() : Array
new Array( length:Number ) : Array
new Array( element0, element1, element2,...elementN ) : Array
Parameters
length
An integer that specifies the number of elements in the array.
element0...elementN
A list of two or more arbitrary values. The values can be of type
Boolean, Number, String, Object, or Array. The first element in an array always has an index or
position of 0.
Note: If only a single numeric parameter is passed to the Array constructor, it is assumed to be
length
and it is converted to an integer using the
Integer()
function.
Returns
A reference to an Array object.
Description
Constructor; lets you create an array. You can use the constructor to create different types of
arrays: an empty array, an array with a specific length but whose elements have undefined values,
or an array whose elements have specific values.
Usage 1: If you don’t specify any parameters, an array with a length of 0 is created.
Usage 2: If you specify only a length, an array is created with
length
number of elements. Each
element’s value is set to
undefined
.
Usage 3: If you use the
element
parameters to specify values, an array is created with
specific values.
Example
Usage 1: The following example creates a new Array object with an initial length of 0:
var my_array:Array = new Array();
trace(my_array.length); // traces 0
Usage 2: The following example creates a new Array object with an initial length of 4:
var my_array:Array = new Array(4);
trace(my_array.length); // returns 4
trace(my_array[0]); // returns undefined
if (my_array[0] == undefined) { // no quotation marks around undefined
trace("undefined is a special value, not a string");
} // traces: undefined is a special value, not a string