Tip: Fire Fox keypress event.

New versions of FireFox allows user to access some keypress properties such as the type, and key code through the "onkeypress" event registration. Not like the old time Netscape, we can access the two properties from the window.Event object.
This is to say, "onkeydown" and "onkeyup" events do not return the two properties at all as expected by some developers (might due to Internet Explorer is returning the two properties?). Some JavaScript code might still be using the old Netscape style which does not work for FireFox.