User Guide

78 Chapter 2: ActionScript Language Reference
= (assignment)
Availability
Flash Player 4.
In Flash 5 or later,
= is an assignment operator, and the == operator is used to evaluate equality. In
Flash 4,
= is a numeric equality operator. Flash 4 files that are brought into the Flash 5 or later
authoring environment undergo a conversion process to maintain data type integrity.
Flash 4 file:
x = y
Converted Flash 5 or later file:
Number(x) == Number(y)
Usage
expression1 = expression2
Parameters
expression1
A variable, element of an array, or property of an object.
expression2 A value of any type.
Returns
The assigned value, expression2.
Description
Operator; assigns the value of expression2 (the parameter on the right) to the variable, array
element, or property in
expression1. Assignment can be either by value or by reference.
Assignment by value copies the actual value of
expression2 and stores it in expression1.
Assignment by value is used when a variable is assigned a number or string literal. Assignment by
reference stores a reference to
expression2 in expression1. Assignment by reference is
commonly used with the
new operator. Use of the new operator creates an object in memory and
a reference to that location in memory is assigned to a variable.
For more information, see “Operator precedence and associativity” in Using ActionScript in
Flash.
Example
The following example uses assignment by value to assign the value of 5 to the variable x.
var x:Number = 5;
The following example uses assignment by value to assign the value "hello" to the variable x:
var x:String;
x = "hello";