Disable A Particular Key in AS3

I know it should be simple, but I can't find a solution to this question.

How do i disable a particular key in AS3?

开发者_如何学运维

e.g. disable 'A' key, or 'Minus' key etc...

Thanks in advance for your help.

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for a DisplayObject: listen to KeyboardEvent.KEY_DOWN and if event.charCode is one you need to restrict call event.stopImmediatePropagation()
for an input TextField: use TextField.restrict property