映射入口 | 函数原型
ON_MESSAGE( <message>, <memberFxn> ) | afx_msg LRESULT memberFxn( WPARAM, LPARAM );
| ON_REGISTERED_MESSAGE( <nMessageVariable>, <memberFxn> ) | afx_msg LRESULT memberFxn( WPARAM, LPARAM );
| ON_THREAD_MESSAGE( <message>, <memberFxn> ) | afx_msg void memberFxn( UINT, LONG );
| ON_REGISTERED_THREAD_MESSAGE( <nMessageVariable>, <memberFxn> ) | afx_msg void memberFxn( UINT, LONG );
| |