Some Error when compiling a VC6 code with VS2008... Please Help

Question

Playsound.cpp
BEGIN_MESSAGE_MAP(PlaySound1, CWinThread)
        ON_THREAD_MESSAGE(WM_PLAYSOUND_STARTPLAYING, OnStartPlaying)

 END_MESSAGE_MAP()

Error

playsound.cpp(38) : error C2440: 'static_cast' : cannot convert from 'LRESULT (__thiscall PlaySound1::* )(WPARAM,LPARAM)' to 'void (__thiscall CWinThread::* )(WPARAM,LPARAM)'

1>        None of the functions with this name in scope match the target type

 

I tried to put the whole source and header files .. but the page can't disply them all

can anyone help :)

Answer 1

Your message handler function signature is wrong.  Its return type should be void.

VC6 did not detect errors in message handler signatures.

Answer 2

First of all ... Thanks Mr.Scott for the very very fast answer :)

This is the link to the complete project. If u please, download and compile it. There are a few errors that I have solved, but I couldn’t solve the error that I showed before cause I have a little experience in programming…. Can anyone exactly show me how to fix this problem ??

http://www.codeproject.com/KB/IP/videonet/VideoNet_src.zip

Thanks All

Answer 3

For the OnStartPlaying function change LRESULT to void

At the end of the function remove the "return" statement.

 

Answer 4

Most people are not going to download a whole project.

In your PlaySound1 class definition in playsound.h, you must a have a method that is declared

LRESULT OnStartPlaying(WPARAM wParam, LPARAM lParam);

or maybe

afx_msg LRESULT OnStartPlaying(WPARAM wParam, LPARAM lParam);

Change LRESULT to void.

Likewise, in playsound.cpp you must have the implementation

LRESULT PlaySound1::OnStartPlaying(WPARAM wParam, LPARAM lParam)
{
   // code is here
}

Again, replace LRESULT by void. And change the return statements in the function to eliminate the return value.

This was actually a breaking change in VC7 and later compared to VC6.

---

David Wilkinson | Visual C++ MVP

Answer 5

thanks all,

all things work perfectly

thanks again :)

Answer 6

Would you mind selecting Scott's and/or Dave's posts as your answer, then? Thanks.