ActionScript for Flash MX: The Definitive Guide, Second Edition

Key.isDown() Method

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_root.gotoAndStop("mainInterface");

}

}

Key.addListener(keyListener);

See Also

Button keyPress, Key.getAscii( ), Key.isDown( ); Appendix B

Key.isDown() Method

check whether a specific key is currently depressed

Flash 5

Key.isDown(keycode)

Arguments

keycode A number representing the keycode of the key to check. Can also be one of

the

Key constants (e.g., Key.UP, Key.BACKSPACE).

Returns

A Boolean indicating whether the key specified by keycode is currently depressed (true)or

not (

false).

Description

The isDown( ) method tells us whether the key specified by keycode is currently being

pressed, such as:

trace(isDown(65)); // Displays: true if the "A" key is depressed during the test

It offers immediate access to the state of the keyboard and is best used with systems that

require constant key-based input or that detect the pressing of simultaneous keys.

The isDown( ) method offers three advantages over getCode( ) and getAscii( ); it can:

• Detect the state of modifier keys such as Ctrl, Command, Shift, and Option, which do

not trigger keyboard events on their own. (To determine whether the Caps Lock, Num

Lock, and Scroll Lock keys are in their locked (down) state, use isToggled( ) instead.)

• Detect the state of arbitrary keys, allowing programmers ...