Is there Any way to handle the crtl + Alt + Del Key combination. Take for instance in a quiz application (Win Forms ), the user should not be able to switch to other windows till the test is over.
I'm able to capture the ctrl and alt key strokes individually, using c# standard properties. but once they user hits the del key . The control goes out of my appliation and windows handles it.
Any thoughts would be helpful.
thanks.
I don't think this is a good approach.
You are developing an application for the user and should not try to hinder his general actions.
For Alt+Ctrl+Del key combination read this article.
AFAIK, Ctrl+Alt+Del generates a hardware interrupt and cannot be handled through software applications. Probably this can be handled through system-level keyboard hooks but I am not so sure about that either.
Have a look here:
http://www.thescarms.com/vbasic/StopReBoot.aspx
Essentially for Win9x we trick system to think that the screensaver is running (which disables Ctrl-Alt-Delete sequence) and for WinNT we remap keyboard.
If it proves impossible to stop the effects of ctrl-alt-delete but you can at least detect that ctrl-alt-delete has been pressed then you could always flag any occurrences and penalize the offender in an appropriate way.
Based on other answers, it seems that this is possible to do. Although I highly discourage this. Take for instance that your program should for some reason hang (god forbid...). Then you would have the situation that the only thing the user can do is to turn off the computer with the power button (or pull the plug...).
It is for a good reason that this is difficult to do, and the methods are poorly documented...
The only way this looks like the way to go, is the comment from Pierre-Alain Vigeant if this is a kiosk computer or something. Then it would actually make sense to do this!
Set Form.TopMost to true, call Form.Activate() every millisecond and raise the process and entry thread priorities.
(Lo and behold the poor user which your application crashes on.)