Is there a resize event for screen in Windows

I have a simple app that changes numlock state when I'm connected to a docking station. The problem is I don't know how to detect when a second monitor is connected (and disconnected) so that I only set the state once it is connected. So I'm looking for Screen.Resize event or similar.

I'm working on Windows 7 so I开发者_运维百科 will settle for Windows 7 only solution though I'd like a more universal solution if possible.

Another thing - this should be a VS 2008 C++ Express compatible solution ;-), but I have access to full VS at work so MFC requirement would be manageable too.

WM_DISPLAYCHANGE