这个是什么错误
Compiling...Ex05_3.cpp
MainFrm.cpp
C:\Program Files (x86)\Microsoft Visual Studio\MyProjects\Ex05_3\MainFrm.cpp(111) : error C2511: 'OnContextMenu' : overloaded member function 'void (class CWnd *,class CPoint)' not found in 'CMainFrame'
c:\program files (x86)\microsoft visual studio\myprojects\ex05_3\mainfrm.h(12) : see declaration of 'CMainFrame'
Generating Code...
Error executing cl.exe.
Ex05_3.exe - 1 error(s), 0 warning(s)