ActionScript® 3.0 Reference for the Adobe® Flash® Platform
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flash.events 

KeyboardEvent  - AS3

Packageflash.events
Classpublic class KeyboardEvent
InheritanceKeyboardEvent Inheritance Event Inheritance Object

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

A KeyboardEvent object id dispatched in response to user input through a keyboard. There are two types of keyboard events: KeyboardEvent.KEY_DOWN and KeyboardEvent.KEY_UP

Because mappings between keys and specific characters vary by device and operating system, use the TextEvent event type for processing character input.

To listen globally for key events, listen on the Stage for the capture and target or bubble phase.

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Related API Elements



Public Properties
 PropertyDefined By
  altKey : Boolean
Indicates whether the Alt key is active (true) or inactive (false) on Windows; indicates whether the Option key is active on Mac OS.
KeyboardEvent
 Inheritedbubbles : Boolean
[read-only] Indicates whether an event is a bubbling event.
Event
 Inheritedcancelable : Boolean
[read-only] Indicates whether the behavior associated with the event can be prevented.
Event
  charCode : uint
Contains the character code value of the key pressed or released.
KeyboardEvent
  commandKey : Boolean
Indicates whether the Command key is active (true) or inactive (false).
KeyboardEvent
 Inheritedconstructor : Object
A reference to the class object or constructor function for a given object instance.
Object
  controlKey : Boolean
Indicates whether the Control key is active (true) or inactive (false).
KeyboardEvent
  ctrlKey : Boolean
On Windows and Linux, indicates whether the Ctrl key is active (true) or inactive (false); On Mac OS, indicates whether either the Ctrl key or the Command key is active.
KeyboardEvent
 InheritedcurrentTarget : Object
[read-only] The object that is actively processing the Event object with an event listener.
Event
 InheritedeventPhase : uint
[read-only] The current phase in the event flow.
Event
  keyCode : uint
The key code value of the key pressed or released.
KeyboardEvent
  keyLocation : uint
Indicates the location of the key on the keyboard.
KeyboardEvent
  shiftKey : Boolean
Indicates whether the Shift key modifier is active (true) or inactive (false).
KeyboardEvent
 Inheritedtarget : Object
[read-only] The event target.
Event
 Inheritedtype : String
[read-only] The type of event.
Event
Public Methods
 MethodDefined By
  
KeyboardEvent(type:String, bubbles:Boolean = true, cancelable:Boolean = false, charCodeValue:uint = 0, keyCodeValue:uint = 0, keyLocationValue:uint = 0, ctrlKeyValue:Boolean = false, altKeyValue:Boolean = false, shiftKeyValue:Boolean = false, controlKeyValue:Boolean = false, commandKeyValue:Boolean = false)
Creates an Event object that contains specific information about keyboard events.
KeyboardEvent
  
[override] Creates a copy of the KeyboardEvent object and sets the value of each property to match that of the original.
KeyboardEvent
 Inherited
formatToString(className:String, ... arguments):String
A utility function for implementing the toString() method in custom ActionScript 3.0 Event classes.
Event
 Inherited
Indicates whether an object has a specified property defined.
Object
 Inherited
Checks whether the preventDefault() method has been called on the event.
Event
 Inherited
Indicates whether an instance of the Object class is in the prototype chain of the object specified as the parameter.
Object
 Inherited
Cancels an event's default behavior if that behavior can be canceled.
Event
 Inherited
Indicates whether the specified property exists and is enumerable.
Object
 Inherited
Sets the availability of a dynamic property for loop operations.
Object
 Inherited
Prevents processing of any event listeners in the current node and any subsequent nodes in the event flow.
Event
 Inherited
Prevents processing of any event listeners in nodes subsequent to the current node in the event flow.
Event
 Inherited
Returns the string representation of this object, formatted according to locale-specific conventions.
Object
  
[override] Returns a string that contains all the properties of the KeyboardEvent object.
KeyboardEvent
  
Indicates that the display should be rendered after processing of this event completes, if the display list has been modified
KeyboardEvent
 Inherited
Returns the primitive value of the specified object.
Object
Public Constants
 ConstantDefined By
  KEY_DOWN : String = "keyDown"
[static] The KeyboardEvent.KEY_DOWN constant defines the value of the type property of a keyDown event object.
KeyboardEvent
  KEY_UP : String = "keyUp"
[static] The KeyboardEvent.KEY_UP constant defines the value of the type property of a keyUp event object.
KeyboardEvent
Property Detail

altKey

property
altKey:Boolean

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

Indicates whether the Alt key is active (true) or inactive (false) on Windows; indicates whether the Option key is active on Mac OS.



Implementation
    public function get altKey():Boolean
    public function set altKey(value:Boolean):void

charCode

property 
charCode:uint

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

Contains the character code value of the key pressed or released. The character code values are English keyboard values. For example, if you press Shift+3, charCode is # on a Japanese keyboard, if you press Shift+2, charCode is



Implementation
    public function get charCode():uint
    public function set charCode(value:uint):void

Related API Elements

commandKey

property 
commandKey:Boolean

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Lite 4

Indicates whether the Command key is active (true) or inactive (false). Supported for Mac OS only. On Mac OS, the commandKey property has the same value as the ctrlKey property.



Implementation
    public function get commandKey():Boolean
    public function set commandKey(value:Boolean):void

controlKey

property 
controlKey:Boolean

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Lite 4

Indicates whether the Control key is active (true) or inactive (false). On Windows and Linux, this is also true when the Ctrl key is active.



Implementation
    public function get controlKey():Boolean
    public function set controlKey(value:Boolean):void

ctrlKey

property 
ctrlKey:Boolean

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

On Windows and Linux, indicates whether the Ctrl key is active (true) or inactive (false); On Mac OS, indicates whether either the Ctrl key or the Command key is active.



Implementation
    public function get ctrlKey():Boolean
    public function set ctrlKey(value:Boolean):void

keyCode

property 
keyCode:uint

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

The key code value of the key pressed or released.

Note: When an input method editor (IME) is running, keyCode does not report accurate key codes.



Implementation
    public function get keyCode():uint
    public function set keyCode(value:uint):void

Related API Elements

keyLocation

property 
keyLocation:uint

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

Indicates the location of the key on the keyboard. This is useful for differentiating keys that appear more than once on a keyboard. For example, you can differentiate between the left and right Shift keys by the value of this property: KeyLocation.LEFT for the left and KeyLocation.RIGHT for the right. Another example is differentiating between number keys pressed on the standard keyboard (KeyLocation.STANDARD) versus the numeric keypad (KeyLocation.NUM_PAD).



Implementation
    public function get keyLocation():uint
    public function set keyLocation(value:uint):void

shiftKey

property 
shiftKey:Boolean

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

Indicates whether the Shift key modifier is active (true) or inactive (false).



Implementation
    public function get shiftKey():Boolean
    public function set shiftKey(value:Boolean):void
Constructor Detail

KeyboardEvent

()Constructor
public function KeyboardEvent(type:String, bubbles:Boolean = true, cancelable:Boolean = false, charCodeValue:uint = 0, keyCodeValue:uint = 0, keyLocationValue:uint = 0, ctrlKeyValue:Boolean = false, altKeyValue:Boolean = false, shiftKeyValue:Boolean = false, controlKeyValue:Boolean = false, commandKeyValue:Boolean = false)

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

Creates an Event object that contains specific information about keyboard events. Event objects are passed as parameters to event listeners.

Parameters
type:String — The type of the event. Possible values are: KeyboardEvent.KEY_DOWN and KeyboardEvent.KEY_UP
 
bubbles:Boolean (default = true) — Determines whether the Event object participates in the bubbling stage of the event flow.
 
cancelable:Boolean (default = false) — Determines whether the Event object can be canceled.
 
charCodeValue:uint (default = 0) — The character code value of the key pressed or released. The character code values returned are English keyboard values. For example, if you press Shift+3, the Keyboard.charCode() property returns # on a Japanese or a German keyboard, just as it does on an English keyboard.
 
keyCodeValue:uint (default = 0) — The key code value of the key pressed or released.
 
keyLocationValue:uint (default = 0) — The location of the key on the keyboard.
 
ctrlKeyValue:Boolean (default = false) — On Windows, indicates whether the Ctrl key is activated. On Mac, indicates whether either the Ctrl key or the Command key is activated.
 
altKeyValue:Boolean (default = false) — Indicates whether the Alt key modifier is activated (Windows only).
 
shiftKeyValue:Boolean (default = false) — Indicates whether the Shift key modifier is activated.
 
controlKeyValue:Boolean (default = false) — Indicates whether the Control key is activated on Mac, and whether the Control or Ctrl keys are activated on WIndows and Linux.
 
commandKeyValue:Boolean (default = false) — Indicates whether the Command key is activated (Mac only).

Related API Elements

Method Detail

clone

()method
override public function clone():Event

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

Creates a copy of the KeyboardEvent object and sets the value of each property to match that of the original.

Returns
Event — A new KeyboardEvent object with property values that match those of the original.

toString

()method 
override public function toString():String

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

Returns a string that contains all the properties of the KeyboardEvent object. The string is in the following format:

[KeyboardEvent type=value bubbles=value cancelable=value ... shiftKey=value]

Returns
String — A string that contains all the properties of the KeyboardEvent object.

updateAfterEvent

()method 
public function updateAfterEvent():void

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

Indicates that the display should be rendered after processing of this event completes, if the display list has been modified

Constant Detail

KEY_DOWN

Constant
public static const KEY_DOWN:String = "keyDown"

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

The KeyboardEvent.KEY_DOWN constant defines the value of the type property of a keyDown event object.

This event has the following properties:

PropertyValue
bubblestrue
cancelabletrue in AIR, false in Flash Player; in AIR, canceling this event prevents the character from being entered into a text field.
charCodeThe character code value of the key pressed or released.
commandKeytrue on Mac if the Command key is active. Otherwise, false
controlKeytrue on Windows and Linux if the Ctrl key is active. true on Mac if either the Control key is active. Otherwise, false
ctrlKeytrue on Windows and Linux if the Ctrl key is active. true on Mac if either the Ctrl key or the Command key is active. Otherwise, false.
currentTargetThe object that is actively processing the Event object with an event listener.
keyCodeThe key code value of the key pressed or released.
keyLocationThe location of the key on the keyboard.
shiftKeytrue if the Shift key is active; false if it is inactive.
targetThe InteractiveObject instance with focus. The target is not always the object in the display list that registered the event listener. Use the currentTarget property to access the object in the display list that is currently processing the event.

Related API Elements

KEY_UP

Constant 
public static const KEY_UP:String = "keyUp"

Language Version: ActionScript 3.0
Runtime Versions: AIR 1.0, Flash Player 9, Flash Lite 4

The KeyboardEvent.KEY_UP constant defines the value of the type property of a keyUp event object.

This event has the following properties:

PropertyValue
bubblestrue
cancelablefalse; there is no default behavior to cancel.
charCodeContains the character code value of the key pressed or released.
commandKeytrue on Mac if the Command key is active. Otherwise, false
controlKeytrue on Windows and Linux if the Ctrl key is active. true on Mac if either the Control key is active. Otherwise, false
ctrlKeytrue on Windows if the Ctrl key is active. true on Mac if either the Ctrl key or the Command key is active. Otherwise, false.
currentTargetThe object that is actively processing the Event object with an event listener.
keyCodeThe key code value of the key pressed or released.
keyLocationThe location of the key on the keyboard.
shiftKeytrue if the Shift key is active; false if it is inactive.
targetThe InteractiveObject instance with focus. The target is not always the object in the display list that registered the event listener. Use the currentTarget property to access the object in the display list that is currently processing the event.

Related API Elements

KeyboardEventExample.as

The following example uses the KeyboardEventExample class to show keyboard events and their listener functions. The example carries out the following tasks:
  1. It creates a new Sprite instance named child.
  2. It declares properties for later use in setting a square's background color and size.
  3. Using methods of Sprite, it draws a light-blue square that it displays on the Stage at default coordinates (0,0) by calling the addChild() method.
  4. It adds one mouse event and two keyboard type event listeners:
    • click/clickHandler which is dispatched when you click on the square to set focus on the child sprite so it can listen for keyboard events.
    • keyDown/keyDownHandler which is dispatched whenever any key is pressed. The subscriber method prints information about the event using the trace() statement.
    • keyUp/keyUpHandler which is dispatched when a key is released.

When you test this example, you need to click the square first for the keyboard events to work.

Also, if you are using the Test Movie command in Flash, the authoring interface may respond to certain keys instead of the event listeners attached to the child sprite.

package {
    import flash.display.Sprite;
    import flash.display.DisplayObject;
    import flash.events.*;

    public class KeyboardEventExample extends Sprite {
        private var child:Sprite = new Sprite();
        private var bgColor:uint = 0x00CCFF;
        private var size:uint = 80;

        public function KeyboardEventExample() {
            child.graphics.beginFill(bgColor);
            child.graphics.drawRect(0, 0, size, size);
            child.graphics.endFill();
            addChild(child);
            child.addEventListener(MouseEvent.CLICK, clickHandler);
            child.addEventListener(KeyboardEvent.KEY_DOWN, keyDownHandler);
            child.addEventListener(KeyboardEvent.KEY_UP, keyUpHandler);
            
        }

        private function clickHandler(event:MouseEvent):void {
            stage.focus = child;
        }

        private function keyDownHandler(event:KeyboardEvent):void {
            trace("keyDownHandler: " + event.keyCode);
            trace("ctrlKey: " + event.ctrlKey);
            trace("keyLocation: " + event.keyLocation);
            trace("shiftKey: " + event.shiftKey);
            trace("altKey: " + event.altKey);

        }

        private function keyUpHandler(event:KeyboardEvent):void {
            trace("keyUpHandler: " + event.keyCode);
        }
        
        
    }
}