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Error 13 error C2440 when converting MFC6 app to MFC8...

Last Modified: 2013-12-14
I have an old MFC6 application that i have ported across to MFC 8 (2005).

It fails compilation with the following message

Error 13 error C2440: 'static_cast' : cannot convert from 'LRESULT (__thiscall CMyAppName::* ) (WPARAM,LPARAM)' to 'LRESULT (__thiscall CWnd::* )(WPARAM,LPARAM)' d:\source\MyApp\app1.cpp 164

The CPP file has the following:
LRESULT CMyAppName::OnMyMessage1(WPARAM wParam, LPARAM lParam)
   ULONG p1 = static_cast<ULONG> ( wParam );
   ULONG p2 = static_cast<ULONG> ( lParam );

the Header file has the following:
afx_msg LRESULT OnMyMessage1(WPARAM wParam, LPARAM lParam);
There are words about this all over the internet but no simple step guides as to how to convert it!

Any help would be appreciated.

Best regards,

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You'll probably have to change your function to

afx_msg void OnMyMessage1(WPARAM wParam, LPARAM lParam); // <- doesn't return anything

If you have to have a return value, only solution I see is to push this function into a class that derives from CWnd.



Thanks for the exceptionally fastest response!


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