How to evaluate keycode onKeyDown in javascript

[Bright Sun]

Hello,

I want to know the evaluated key value when a onKeyDown event is sent.
But it is really hard to get it. Even if I use
String.fromCharCode(event.keyCode)
it will not work when I press the right hand small keyboard. So I want
to know any other method to get the return value when a key pressed.

Any idea?
Thanks in ahead for reply me.