C# RegisterClassEx/WNDCLASSEX problem

Hello all,

I am having trouble registering a new window class in C# using RegisterClassEx.  My application already heavily uses the WinAPI via pInvoke (i.e. DllImport statements) for other functions, and that part isn't the problem, I don't think (but am open to the possibility.)

Basically, when I call CreateWindowEx, it fails with error 1407, which basically says that my class name is undefined (which I agree with.)  I simply can't seem to figure out the WNDCLASSEX structure and how to use it in C#.  Could anyone please post and/or send me C# sample code that will successfully register a new window class (named, for example's sake "sample_window") that will allow a call to CreateWindowEx similar to the following to succeed??

            IntPtr myNewSampleWindowHWND = CreateWindowEx(WS_EX_TOPMOST, "sample_window", "", WS_VISIBLE, 0, 0, 500, 500, this.Handle, IntPtr.Zero, IntPtr.Zero, IntPtr.Zero);

My goal is to create a blank (in the sense of WinAPI programming) topmost window that I can get a Graphics object from and draw a rectangle on.  Other than what I specifically draw, I would like the window to be completely "blank" (A.K.A  no menu or title bar, etc.)  I only want what I draw to be displayed.  Ultimately, the app should be able to destroy the window using something like:

DestroyWindow(myNewSampleWindowHWND)

Does that make sense?  I know how to do this in VC++, but am trying to stick to C# for code-management purposes.  I have tried and tried to no avail to get this to work in C#, and I could really use some help.

Thanks so much!!!
Kendell
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