WndProc message = 49619 -what is it?

Question

I'm debugging a dragging bug in wpf and have subscribed to wndproc. I'm getting a message ID of 49619 with wparam=0 and lparam=0. I've exhausted my google efforts and have been unable to uncover what the name of this window message is.

If you know, great. If you can provide a website that includes it in its listing of window messages, that's even better.

hex value = 0xC1D3

Answer 1

Take a look at WM_USER. http://msdn.microsoft.com/en-us/library/windows/desktop/ms644931(v=vs.85).aspx

RegisterWindowMessage

Message numbers in the fourth range (0xC000 through 0xFFFF) are defined at run time when an application calls the RegisterWindowMessage function to retrieve a message number for a string. All applications that register the same string can use the associated message number for exchanging messages. The actual message number, however, is not a constant and cannot be assumed to be the same between different sessions.