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Package flash.utils 

The flash.utils package contains a variety of package-level functions for timing code execution, retrieving information about classes and objects, and converting escape characters.
Public Methods
 FunctionDefined By
  
Cancels a specified setInterval() call.
flash.utils
  
Cancels a specified setTimeout() call.
flash.utils
  
Produces an XML object that describes the ActionScript object named as the parameter of the method.
flash.utils
  
Returns an escaped copy of the input string encoded as either UTF-8 or system code page, depending on the value of System.useCodePage.
flash.utils
  
Returns a reference to the class object of the class specified by the name parameter.
flash.utils
  
Returns the fully qualified class name of an object.
flash.utils
  
Returns the fully qualified class name of the base class of the object specified by the value parameter.
flash.utils
  
Used to compute relative time.
flash.utils
  
setInterval(closure:Function, delay:Number, ... arguments):uint
Runs a function at a specified interval (in milliseconds).
flash.utils
  
setTimeout(closure:Function, delay:Number, ... arguments):uint
Runs a specified function after a specified delay (in milliseconds).
flash.utils
  
Returns an unescaped copy of the input string, which is decoded from either system code page page or UTF-8 depending on the value of System.useCodePage.
flash.utils
Function detail

clearInterval

()function
public function clearInterval(id:uint):void

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

Cancels a specified setInterval() call.

Parameters

id:uint — The ID of the setInterval() call, which you set to a variable, as in the following:

See also


Example  ( How to use this example )

The following example uses the setInterval() method to create a timed interval, calling the myRepeatingFunction() method after regular intervals of one second.

Each call of the myRepeatingFunction method increments the counter property, and when it equals the stopCount property, the clearInterval() method is called with the property intervalId which is a reference id to the interval that was created earlier.

package {
    import flash.display.Sprite;
    import flash.utils.*;

    public class ClearIntervalExample extends Sprite {
        private var intervalDuration:Number = 1000; // duration between intervals, in milliseconds
        private var intervalId:uint;
        private var counter:uint     = 0;
        private var stopCount:uint     = 3;
        
        public function ClearIntervalExample() {
            intervalId = setInterval(myRepeatingFunction, intervalDuration, "Hello", "World");
        }

        public function myRepeatingFunction():void {
            trace(arguments[0] + " " + arguments[1]);

            counter++;
            if(counter == stopCount) {
                trace("Clearing Interval");
                clearInterval(intervalId);    
            }
        }
    }
}

clearTimeout

()function 
public function clearTimeout(id:uint):void

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

Cancels a specified setTimeout() call.

Parameters

id:uint — The ID of the setTimeout() call, which you set to a variable, as in the following:

See also


Example  ( How to use this example )

The following example uses the setTimeout() method to call another method following a specified delay period.

A loop is created to count to one million. If the computer can process this request faster than a second can expire, clearTimeout() will remove the setTimeout() request, and myDelayedFunction() will not be called.

package {
    import flash.display.Sprite;
    import flash.utils.*;

    public class ClearTimeoutExample extends Sprite {
        private var delay:Number = 1000; // delay before calling myDelayedFunction
        private var intervalId:uint;
        private var count:uint = 1000000;
        
        public function ClearTimeoutExample() {
            intervalId = setTimeout(myDelayedFunction, delay);
            startCounting();
        }

        public function startCounting():void {
            var i:uint = 0;
            do {
                if(i == count-1) {
                    clearTimeout(intervalId);
                    trace("Your computer can count to " + count + " in less than " + delay/1000 + " seconds.");    
                }
                i++;
            } while(i < count)            
        }
        
        public function myDelayedFunction():void {
            trace("Time expired.");
        }
    }
}

describeType

()function 
public function describeType(value:*):XML

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

Produces an XML object that describes the ActionScript object named as the parameter of the method. This method implements the programming concept of reflection for the ActionScript language.

If the value parameter is an instance of a type, the returned XML object includes all the instance properties of that type, but does not include any static properties. You can check for this condition when you parse the XML object by examining the value of the <type> tag's isStatic attribute, which is false when the value parameter is an instance of a type.

To obtain the static properties of a type, pass the type itself for the value parameter. The returned XML object includes not only the type's static properties, but also all of its instance properties. The instance properties are nested inside a tag named <factory> to distinguish them from the static properties. In this case, the isStatic attribute of the <type> tag is true.

Note: If you need only to traverse an object's inheritance hierarchy and do not need the other information provided by describeType(), use the getQualifiedClassName() and getQualifiedSuperclassName() functions instead.

The following table describes some of the tags and attributes of the XML object generated by describeType() (all class and interface names returned are in fully qualified format):

TagAttributeDescription
<type> The root tag of the XML object.
 nameThe name of the ActionScript object's data type.
 baseThe immediate superclass of the ActionScript object's defining class. If the ActionScript object is a class object, the value is Class.
 isDynamictrue if the ActionScript object's defining class is dynamic; false otherwise. If the ActionScript object is a class object, the value is true because the Class class is dynamic.
 isFinaltrue if the ActionScript object's defining class is final; false otherwise.
 isStatictrue if the ActionScript object is a class object or constructor function; false otherwise. This attribute is named isStatic because if it is true, any tags that are not nested inside the factory tag are static.
<extendsClass> There is a separate extendsClass tag for each superclass of the ActionScript object's defining class.
 typeThe name of a superclass that the ActionScript object's defining class extends.
<implementsInterface> There is a separate implementsInterface tag for each interface implemented by the ActionScript object's defining class or any of its superclasses.
 typeThe name of an interface that the ActionScript object's defining class implements.
<accessor> An accessor is a property defined by getter and setter functions.
 nameThe name of the accessor.
 accessThe access rights of the property. Possible values include readonly, writeonly, and readwrite.
 typeThe data type of the property.
 declaredByThe class that contains the associated getter or setter functions.
<constant> A constant is a property defined with the const statement.
 nameThe name of the constant.
 typeThe data type of the constant.
<method> A method is a function declared as part of a class definition.
 nameThe name of the method.
 declaredByThe class that contains the method definition.
 returnTypeThe data type of the method's return value.
<parameter> There is a separate parameter tag for each parameter that a method defines. This tag is always nested inside a <method> tag.
 indexA number corresponding to the order in which the parameter appears in the method's parameter list. The first parameter has a value of 1.
 typeThe data type of the parameter.
 optionaltrue if the parameter is optional; false otherwise.
<variable> A variable is a property defined with the var statement.
 nameThe name of the variable.
 typeThe data type of the variable.
<factory> If the ActionScript object is a class object or constructor function, all instance properties and methods are nested inside this tag. If the isStatic attribute of the <type> tag is true, all properties and methods that are not nested within the <factory> tag are static. This tag appears only if the ActionScript object is a class object or constructor function.

Parameters

value:* — The object for which a type description is desired. Any ActionScript value may be passed to this method including all available ActionScript types, object instances, primitive types such as uint, and class objects.

Returns
XML — An XML object containing details about the object that was passed in as a parameter. It provides the following information about the object:
  • The class of the object
  • The attributes of the class
  • The inheritance tree from the class to its base classes
  • The interfaces implemented by the class
  • The declared instance properties of the class
  • The declared static properties of the class
  • The instance methods of the class
  • The static methods of the class
  • For each method of the class, the name, number of parameters, return type, and parameter types

Note: describeType() only shows public properties and methods, and will not show properties and methods that are private, package internal or in custom namespaces.

See also


Example  ( How to use this example )

package {
    import flash.display.Sprite;
    import flash.utils.describeType;
    
    public class DescribeTypeExample extends Sprite {
        public function DescribeTypeExample() {
            var child:Sprite = new Sprite();
            var description:XML = describeType(child);
            trace(description..accessor.@name.toXMLString());
        }
    }
}

escapeMultiByte

()function 
public function escapeMultiByte(value:String):String

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

Returns an escaped copy of the input string encoded as either UTF-8 or system code page, depending on the value of System.useCodePage. Use of System.useCodePage allows legacy content encoded in local code pages to be accessed by the player, but only on systems using that legacy code page. For example, Japanese data encoded as Shift-JIS will only be escaped and unescaped properly on an OS using a Japanese default code page.

Parameters

value:String — The string to be escaped.

Returns
String — An escaped copy of the input string. If System.useCodePage is true, the escaped string is encoded in the system code page. If System.useCodePage is false, the escaped string is encoded in UTF-8. For example, the input string "Crüe" will be escaped as "Cr%C3%BCe" on all systems if System.useCodePage is false. If system.useCodePage is true, and the system uses a Latin code page, "Crüe" will be escaped as "Cr%FCe". If the system uses a non Latin code page that does not contain the letter 'ü' the result will probably be "Cr?e".

getDefinitionByName

()function 
public function getDefinitionByName(name:String):Object

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

Returns a reference to the class object of the class specified by the name parameter.

Parameters

name:String — The name of a class.

Returns
Object — Returns a reference to the class object of the class specified by the name parameter.

Throws
ReferenceError — No public definition exists with the specified name.

Example  ( How to use this example )

The following example uses the class GetDefinitionByNameExample to create an orange square on the stage. This is accomplished using the following steps:
  1. Variables for the background color of orange and size of 80 pixels are declared, which will later be used in drawing the square.
  2. Within the constructor, a variable ClassReference of type Class is assigned to Sprite.
  3. An instance of ClassReference called instance is instantiated.
  4. Since instance is, by reference, a Sprite object, a square can be drawn and added to the display list using the methods available to Sprite.
package {
    import flash.display.DisplayObject;
    import flash.display.Sprite;
    import flash.utils.getDefinitionByName;

    public class GetDefinitionByNameExample extends Sprite {
        private var bgColor:uint = 0xFFCC00;
        private var size:uint = 80;

        public function GetDefinitionByNameExample() {
            var ClassReference:Class = getDefinitionByName("flash.display.Sprite") as Class;
            var instance:Object = new ClassReference();
            instance.graphics.beginFill(bgColor);
            instance.graphics.drawRect(0, 0, size, size);
            instance.graphics.endFill();
            addChild(DisplayObject(instance));
        }
    }
}

getQualifiedClassName

()function 
public function getQualifiedClassName(value:*):String

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

Returns the fully qualified class name of an object.

Parameters

value:* — The object for which a fully qualified class name is desired. Any ActionScript value may be passed to this method including all available ActionScript types, object instances, primitive types such as uint, and class objects.

Returns
String — A string containing the fully qualified class name.

See also

getQualifiedSuperclassName

()function 
public function getQualifiedSuperclassName(value:*):String

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

Returns the fully qualified class name of the base class of the object specified by the value parameter. This function provides a quicker way of retrieving the base class name than describeType(), but also doesn't provide all the information describeType() does.

After you retrieve the name of a class with this function, you can convert the class name to a class reference with the getDefinitionByName() function.

Note: This function restricts itself to instance hierarchies, whereas the describeType() function uses class object hierarchies if the value parameter is a data type. Calling describeType() on a data type returns the superclass based on the class object hierarchy, in which all class objects inherit from Class. The getQualifiedSuperclassName() function, however, ignores the class object hierarchy and returns the superclass based on the more familiar instance hierarchy. For example, calling getQualifiedSuperclassName(String) returns Object although technically the String class object inherits from Class. In other words, the results are the same whether you use an instance of a type or the type itself.

Parameters

value:* — Any value.

Returns
String — A fully qualified base class name, or null if none exists.

See also

getTimer

()function 
public function getTimer():int

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

Used to compute relative time. For a Flash runtime processing ActionScript 3.0, this method returns the number of milliseconds that have elapsed since the Flash runtime virtual machine for ActionScript 3.0 (AVM2) started. For a Flash runtime processing ActionScript 2.0, this method returns the number of milliseconds since the Flash runtime began initialization. Flash runtimes use two virtual machines to process ActionScript. AVM1 is the ActionScript virtual machine used to run ActionScript 1.0 and 2.0. AVM2 is the ActionScript virtual machine used to run ActionScript 3.0. The getTimer() method behavior for AVM1 is different than the behavior for AVM2.

For a calendar date (timestamp), see the Date object.

Returns
int — The number of milliseconds since the runtime was initialized (while processing ActionScript 2.0), or since the virtual machine started (while processing ActionScript 3.0). If the runtime starts playing one SWF file, and another SWF file is loaded later, the return value is relative to when the first SWF file was loaded.

See also


Example  ( How to use this example )

The following example uses the class GetTimerExample to get and print the number of milliseconds since the Flash Player started playing.
package {
    import flash.utils.getTimer;
    import flash.display.Sprite;

    public class GetTimerExample extends Sprite {
        public function GetTimerExample() {
            var duration:uint = getTimer();
            trace("duration: " + duration);
        }
    }
}

setInterval

()function 
public function setInterval(closure:Function, delay:Number, ... arguments):uint

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

Runs a function at a specified interval (in milliseconds).

Instead of using the setInterval() method, consider creating a Timer object, with the specified interval, using 0 as the repeatCount parameter (which sets the timer to repeat indefinitely).

If you intend to use the clearInterval() method to cancel the setInterval() call, be sure to assign the setInterval() call to a variable (which the clearInterval() function will later reference). If you do not call the clearInterval() function to cancel the setInterval() call, the object containing the set timeout closure function will not be garbage collected.

Parameters

closure:Function — The name of the function to execute. Do not include quotation marks or parentheses, and do not specify parameters of the function to call. For example, use functionName, not functionName() or functionName(param).
 
delay:Number — The interval, in milliseconds.
 
... arguments — An optional list of arguments that are passed to the closure function.

Returns
uint — Unique numeric identifier for the timed process. Use this identifier to cancel the process, by calling the clearInterval() method.

See also


Example  ( How to use this example )

The following example uses the setInterval() method to create a timed interval, calling the myRepeatingFunction() method after regular intervals of one second.
package {
    import flash.display.Sprite;
    import flash.utils.*;

    public class SetIntervalExample extends Sprite {
        private var intervalDuration:Number = 1000; // duration between intervals, in milliseconds
        
        public function SetIntervalExample() {
            var intervalId:uint = setInterval(myRepeatingFunction, intervalDuration, "Hello", "World");
        }

        public function myRepeatingFunction():void {
            trace(arguments[0] + " " + arguments[1]);
        }
    }
}

setTimeout

()function 
public function setTimeout(closure:Function, delay:Number, ... arguments):uint

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

Runs a specified function after a specified delay (in milliseconds).

Instead of using this method, consider creating a Timer object, with the specified interval, using 1 as the repeatCount parameter (which sets the timer to run only once).

If you intend to use the clearTimeout() method to cancel the setTimeout() call, be sure to assign the setTimeout() call to a variable (which the clearTimeout() function will later reference). If you do not call the clearTimeout() function to cancel the setTimeout() call, the object containing the set timeout closure function will not be garbage collected.

Parameters

closure:Function — The name of the function to execute. Do not include quotation marks or parentheses, and do not specify parameters of the function to call. For example, use functionName, not functionName() or functionName(param).
 
delay:Number — The delay, in milliseconds, until the function is executed.
 
... arguments — An optional list of arguments that are passed to the closure function.

Returns
uint — Unique numeric identifier for the timed process. Use this identifier to cancel the process, by calling the clearTimeout() method.

See also


Example  ( How to use this example )

The following example uses the setTimeout() method to call another method following a specified delay period.
package {
    import flash.display.Sprite;
    import flash.utils.*;

    public class SetTimeoutExample extends Sprite {
        private var delay:Number = 1000; // delay before calling myDelayedFunction
        
        public function SetTimeoutExample() {
            var intervalId:uint = setTimeout(myDelayedFunction, delay, "Hello", "World");
        }

        public function myDelayedFunction():void {
            trace(arguments[0] + " " + arguments[1]);
        }
    }
}

unescapeMultiByte

()function 
public function unescapeMultiByte(value:String):String

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

Returns an unescaped copy of the input string, which is decoded from either system code page page or UTF-8 depending on the value of System.useCodePage. Use of System.useCodePage allows legacy content encoded in local code pages to be accessed by the player, but only on systems using that legacy code page. For example, Japanese data encoded as Shift-JIS will only be escaped and unescaped properly on an OS using a Japanese default code page.

Parameters

value:String — The escaped string to be unescaped.

Returns
String — An escaped copy of the input string. If System.useCodePage is true, the escaped string is encoded in the system code page. If System.useCodePage is false, the escaped string is encoded in UTF-8. For example, the input string "Crüe" will be escaped as "Cr%C3%BCe" on all systems if System.useCodePage is false. If system.useCodePage is true, and the system uses a Latin code page, "Crüe" will be escaped as "Cr%FCe". If the system uses a non Latin code page that does not contain the letter 'ü' the result will probably be "Cr?e". Unescaping "Cr%C3%BCe" with System.useCodePage set to true will produce different undesired results on different systems, such as "Crüe" on a Latin system. Similarly, unescaping "Cr%FCe" with System.useCodePage set to false could produce "Cre" or "Cr?e" or other variations depending on the code page of the system.