C++ and C# findwindow and sendmessage

[stevus06]

I have two projects in Visual Studio 2008: One a C# app, the other a c++ dll.

I have figured out to get my dll started from the c# app and can confirm it is running along with the C# GUI.

The C++ is using several SendMessage(... ) statements and I have setup a WndProc(ref Message m) { } in my C#.

My problem is the C# code does not seem to be receiving any of my SendMessages from the C++.

I am calling this line first in the C++:

HWND hWnd = ::FindWindow(NU LL, _T("Window name"));

and then using

::SendMessage(h Wnd, WM_COPYDATA, (WPARAM)hTable, (LPARAM)&cds);

to send the message to c#. But how does the C++ know anything about my c# window? Do I need to do something else?

[Plater]

You are trying to use windows message loops to talk back and forth?
Send the c++.DLL the hWND handle of your c# window and use that to send c++ to C#. Sending from C# to C++ will require that a handle from c++ be sent to c# for the message system.