Intercept WM_COPYDATA from C++ program to C#

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Guest

Hi all,
Is it possible intercept WM_COPYDATA that send from a unmanaged application
to managed application ? Compact Framework haven't WndProc event. Is it
possible intercept my WM_COPYDATA througth MessageWindow class ?

Thanks
Stefano
 
Yes, so long as your C++ app is sending to the HWND of the MessageWindow,
not the main window of your application.
You create a class which inherits from MessageWindow, override the WndProc
method and add a handler for WM_COPYDATA you can then use the Marshal class
to copy the COPYDATASTRUCT into managed memory and retrieve the raw data
into a byte[] array or other managed structure.

Peter
 
Ok, thanks very much for answer.
but how retrieve the HWND of the MessageWindow instead the main window from
my C++ app ?

Peter Foot said:
Yes, so long as your C++ app is sending to the HWND of the MessageWindow,
not the main window of your application.
You create a class which inherits from MessageWindow, override the WndProc
method and add a handler for WM_COPYDATA you can then use the Marshal class
to copy the COPYDATASTRUCT into managed memory and retrieve the raw data
into a byte[] array or other managed structure.

Peter

--
Peter Foot
Windows Embedded MVP
www.peterfoot.net | www.inthehand.com

Stefano Magni said:
Hi all,
Is it possible intercept WM_COPYDATA that send from a unmanaged
application
to managed application ? Compact Framework haven't WndProc event. Is it
possible intercept my WM_COPYDATA througth MessageWindow class ?

Thanks
Stefano
Click to expand...
Click to expand...
 
That depends on how your C++ app works, if you wrote it you can implement
the exchange in a number of ways for example:-

Use RegisterWindowMessage to register a unique message id for your app and
then have your MessageWindow broadcast this message and include it's own
hwnd in the wparam
Have a native method call which your managed app P/Invokes into and passes
the hwnd
Set a specific name on your MessageWindow and have your native app use
FindWindow to get the hwnd

Peter

--
Peter Foot
Windows Embedded MVP
http://www.inthehand.com | http://www.peterfoot.net

Stefano Magni said:
Ok, thanks very much for answer.
but how retrieve the HWND of the MessageWindow instead the main window
from
my C++ app ?

Peter Foot said:
Yes, so long as your C++ app is sending to the HWND of the MessageWindow,
not the main window of your application.
You create a class which inherits from MessageWindow, override the
WndProc
method and add a handler for WM_COPYDATA you can then use the Marshal
class
to copy the COPYDATASTRUCT into managed memory and retrieve the raw data
into a byte[] array or other managed structure.

Peter

--
Peter Foot
Windows Embedded MVP
www.peterfoot.net | www.inthehand.com

Stefano Magni said:
Hi all,
Is it possible intercept WM_COPYDATA that send from a unmanaged
application
to managed application ? Compact Framework haven't WndProc event. Is it
possible intercept my WM_COPYDATA througth MessageWindow class ?

Thanks
Stefano
Click to expand...
Click to expand...
Click to expand...
 
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