Detect when users take screenshots of my program

Question

I\'m writing a Windows application. How can I tell when a screenshot is being taken of it? I read about how to detect the hotkey being pressed, but I\'m more worried about t

Answer 1

Another reason why I think it will be impossible to achieve this:

A long time ago, I failed to make a screen capture of the content of Windows Media Player, because (I assumed) WMP streamed that content to the videocard right away. (Fun detail: after pasting the screen capture, the video would continue playing in MS Paint, but saving the image would eventually yield a black square). Anyway, using VNC made it very easy to get the screen capture after all.