Adobe® Flex® 4 Language Reference
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__Global__ 
Boolean 
PackageTop Level
Classpublic final class Boolean
InheritanceBoolean Inheritance Object

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 9, AIR 1.0

A Boolean object is a data type that can have one of two values, either true or false, used for logical operations. Use the Boolean class to retrieve the primitive data type or string representation of a Boolean object.

To create a Boolean object, you can use the constructor or the global function, or assign a literal value. It doesn't matter which technique you use; in ActionScript 3.0, all three techniques are equivalent. (This is different from JavaScript, where a Boolean object is distinct from the Boolean primitive type.)

The following lines of code are equivalent:

var flag:Boolean = true;
var flag:Boolean = new Boolean(true);
var flag:Boolean = Boolean(true);

View the examples



Public Properties
 PropertyDefined By
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
 Inheritedprototype : Object
[static] A reference to the prototype object of a class or function object.
Object
Public Methods
 MethodDefined By
  
Boolean(expression:Object = false)
Creates a Boolean object with the specified value.
Boolean
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
  
Returns the string representation ("true" or "false") of the Boolean object.
Boolean
  
Returns true if the value of the specified Boolean object is true; false otherwise.
Boolean
Constructor Detail

Boolean

()Constructor
public function Boolean(expression:Object = false)

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 9, AIR 1.0

Creates a Boolean object with the specified value. If you omit the expression parameter, the Boolean object is initialized with a value of false. If you specify a value for the expression parameter, the method evaluates it and returns the result as a Boolean value according to the rules in the global Boolean() function.

Parameters
expression:Object (default = false) — Any expression.

See also


Example  ( How to use this example )
The following code creates a new Boolean object, initialized to a value of false called myBoolean:
 var myBoolean:Boolean = new Boolean();
 
Method Detail

toString

()method
AS3 function toString():String

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 9, AIR 1.0

Returns the string representation ("true" or "false") of the Boolean object. The output is not localized, and is "true" or "false" regardless of the system language.

Returns
String — The string "true" or "false".

Example  ( How to use this example )
This example creates a variable of type Boolean and then uses the toString() method to convert the value to a string for use in an array of strings:
     var myStringArray:Array = new Array("yes", "could be");
     var myBool:Boolean = 0;
     myBool.toString();
     myStringArray.push(myBool);
     trace(myStringArray); // yes,could be,false
     

valueOf

()method 
AS3 function valueOf():Boolean

Language Version: ActionScript 3.0
Runtime Versions: Flash Player 9, AIR 1.0

Returns true if the value of the specified Boolean object is true; false otherwise.

Returns
Boolean — A Boolean value.

Example  ( How to use this example )
The following example shows how this method works, and also shows that the value of a new Boolean object is false:
     var myBool:Boolean = new Boolean();
     trace(myBool.valueOf());   // false
     myBool = (6==3+3);
     trace(myBool.valueOf());   // true  
     
BooleanExample.as

The following example toggles and displays each corresponding value for the Boolean object:
 package {
    import flash.display.Sprite;

    public class BooleanExample extends Sprite {
        private var flag:Boolean;

        public function BooleanExample() {
            trace(flag);    // false
            toggle();
            trace(flag);    // true
            toggle();
            trace(flag);    // false
        }
        
        private function toggle():void{
            flag = !flag;
        }
    }
}