MFC消息处理基本机制
MFC的思想是所有类继承自基类CObject，每个类都拥有一个消息映射表和各自的成员
通常开发者自定义的窗口是继承自CDialog的，整个继承链为:
MyDialog->CDialog->CWnd->CCmdTarget->CObject当遇到消息时，会从本类的消息映射表中匹配处理对应消息的函数，如果没有找到则去父类的消息映射表中寻找，以此类推
如果直到CObject类的消息映射表寻找完都没有函数处理消息，则将消息放入默认处理函数中处理（与Windows32API的思想一致）
MFC中消息映射机制流程
MFC中的消息映射机制是在OnWndMsg()这个函数中实现的，而在这个函数里又会去查找相应的消息映射的宏。
以下面MFC工程Draw为例：
OnWndMsg会在CDrawTest.h中查找，看看DECLARE_MESSAGE_MAP()之上，两个afx_msg注释宏之间是否有相应的消息响应函数的原型声明
protected:
//{{AFX_MSG(CDrawView)
afx_msg void OnLButtonDown(UINT nFlags, CPoint point);
//函数OnLButtonDown()的原型声明
//}}AFX_MSG
DECLARE_MESSAGE_MAP() 再到CDrawView.cpp中，看看BEGIN_MESSAGE_MAP()和END_MESSAGE_MAP()这两个宏之间是否有相应的消息映射宏
// CDrawView.cpp
IMPLEMENT_DYNCREATE(CDrawView, CView)
BEGIN_MESSAGE_MAP(CDrawView, CView)
//{{AFX_MSG_MAP(CDrawView)
ON_WM_LBUTTONDOWN() //函数OnLButtonDown()在消息映射宏之中
//}}AFX_MSG_MAP
// Standard printing commands
ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)
ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)
ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)
END_MESSAGE_MAP() 如果通过前两个步骤，找到了消息响应函数，那么接着就会调用该响应函数，对消息进行处理。 如果子类中没有找到消息响应函数，那么就就给基类处理。
MFC中ON_UPDATE_COMMAND_UI和ON_COMMAND消息区别
ON_COMMAND消息是响应打开菜单的命令的
ON_UPDATE_COMMAND_UI是你打开这个菜单时，处理这个菜单的状态，比如选中、变灰等等。
ON_WM_ACTIVATE( ) afx_msg void OnActivate( UINT, CWnd*,BOOL )
ON_WM_ACTIVATEAPP( ) afx_msg void OnActivateApp( BOOL,HANDLE )
ON_WM_ASKCBFORMATNAME( ) afx_msg void OnAskCbFormatName( UINT,LPSTR )
ON_WM_CANCELMODE( ) afx_msg void OnCancelMode( )
ON_WM_CAPTURECHANGED( ) afx_msg void OnCaptureChanged( CWnd* )
ON_WM_CHANGECBCHAIN( ) afx_msg void OnChangeCbChain( HWND, HWND )
ON_WM_CHAR( ) afx_msg void OnChar( UINT, UINT,UINT )
ON_WM_CHARTOITEM( ) afx_msg int OnCharToItem( UINT,CWnd*, UINT )
ON_WM_CHILDACTIVATE( ) afx_msg void OnChildActivate( )
ON_WM_CLOSE( ) afx_msg void OnClose( )
ON_WM_COMPACTING( ) afx_msg void OnCompacting( UINT )
ON_WM_COMPAREITEM( ) afx_msg int OnCompareItem( LPCOMPAREITEMSTRUCT )
ON_WM_CONTEXTMENU( ) afx_msg void OnContextMenu( CWnd*, CPoint )
ON_WM_COPYDATA( ) afx_msg BOOL OnCopyData( CWnd* pWnd, COPYDATASTRUCT* pCopyDataStruct )
ON_WM_CREATE( ) afx_msg int OnCreate( LPCREATESTRUCT )
ON_WM_CTLCOLOR( ) afx_msg HBRUSH OnCtlColor( CDC*, CWnd*, UINT )
ON_WM_DEADCHAR( ) afx_msg void OnDeadChar( UINT, UINT, UINT )
ON_WM_DELETEITEM( ) afx_msg void OnDeleteItem( LPDELETEITEMSTRUCT )
ON_WM_DESTROY( ) afx_msg void OnDestroy( )
ON_WM_DESTROYCLIPBOARD( ) afx_msg void OnDestroyClipboard( )
ON_WM_DEVICECHANGE( ) afx_msg void OnDeviceChange( UINT, DWORD )
ON_WM_DEVMODECHANGE( ) afx_msg void OnDevModeChange( LPSTR )
ON_WM_DRAWCLIPBOARD( ) afx_msg void OnDrawClipboard( )
ON_WM_DRAWITEM( ) afx_msg void OnDrawItem( LPDRAWITEMSTRUCT )
ON_WM_DROPFILES( ) afx_msg void OnDropFiles( HDROP )
ON_WM_ENABLE( ) afx_msg void OnEnable( BOOL )
ON_WM_ENDSESSION( ) afx_msg void OnEndSession( BOOL )
ON_WM_ENTERIDLE( ) afx_msg void OnEnterIdle( UINT,CWnd* )
ON_WM_ERASEBKGND( ) afx_msg BOOL OnEraseBkgnd( CDC * )
ON_WM_FONTCHANGE( ) afx_msg void OnFontChange( )
ON_WM_GETDLGCODE( ) afx_msg UINT OnGetDlgCode( )
ON_WM_GETMINMAXINFO( ) afx_msg void OnGetMinMaxInfo( LPPOINT )
ON_WM_HELPINFO( ) afx_msg BOOL OnHelpInfo( HELPINFO* )
ON_WM_HSCROLL( ) afx_msg void OnHScroll( UINT, UINT,CWnd* )
ON_WM_HSCROLLCLIPBOARD() afx_msg void OnHScrollClipboard( CWnd*, UINT, UINT)
ON_WM_ICONERASEBKGND( ) afx_msg void OnIconEraseBkgnd( CDC* )
ON_WM_INITMENU( ) afx_msg void OnInitMenu( CMenu* )
ON_WM_INITMENUPOPUP( ) afx_msg void OnInitMenuPopup( CMenu*, UINT, BOOL )
ON_WM_KEYDOWN( ) afx_msg void OnKeyDown( UINT, UINT, UINT )
ON_WM_KEYUP( ) afx_msg void OnKeyUp( UINT, UINT, UINT )
ON_WM_KILLFOCUS( ) afx_msg void OnKillFocus( CWnd* )
ON_WM_LBUTTONDBLCLK( ) afx_msg void OnLButtonDblClk( UINT, Cpoint )
ON_WM_LBUTTONDOWN( ) afx_msg void OnLButtonDown( UINT, CPoint )
ON_WM_LBUTTONUP( ) afx_msg void OnLButtonUp( UINT, CPoint )
ON_WM_MBUTTONDBLCLK( ) afx_msg void OnMButtonDblClk( UINT, CPoint )
ON_WM_MBUTTONDOWN( ) afx_msg void OnMButtonDown( UINT, CPoint )
ON_WM_MBUTTONUP( ) afx_msg void OnMButtonUp( UINT, CPoint )
ON_WM_MDIACTIVATE( ) afx_msg void OnMDIActivate( BOOL, CWnd*, CWnd* )
ON_WM_MEASUREITEM( ) afx_msg void OnMeasureItem( LPMEASUREITEMSTRUCT )
ON_WM_MENUCHAR( ) afx_msg LONG OnMenuChar( UINT, UINT, CMenu* )
ON_WM_MENUSELECT( ) afx_msg void OnMenuSelect( UINT, UINT, HMENU )
ON_WM_MOUSEACTIVATE( ) afx_msg int OnMouseActivate( CWnd*, UINT, UINT )
ON_WM_MOUSEMOVE( ) afx_msg void OnMouseMove( UINT, CPoint )
ON_WM_MOUSEWHEEL( ) afx_msg BOOL OnMouseWheel( UINT, short, CPoint )
ON_WM_MOVE( ) afx_msg void OnMove( int, int )
ON_WM_MOVING( ) afx_msg void OnMoving( UINT, LPRECT )
ON_WM_NCACTIVATE( ) afx_msg BOOL OnNcActivate( BOOL )
ON_WM_NCCALCSIZE( ) afx_msg void OnNcCalcSize( BOOL, NCCALCSIZE_PARAMS FAR* )
ON_WM_NCCREATE( ) afx_msg BOOL OnNcCreate( LPCREATESTRUCT )
ON_WM_NCDESTROY( ) afx_msg void OnNcDestroy( )
ON_WM_NCHITTEST( ) afx_msg UINT OnNcHitTest( CPoint )
ON_WM_NCLBUTTONDBLCLK( ) afx_msg void OnNcLButtonDblClk( UINT, CPoint )
ON_WM_NCLBUTTONDOWN( ) afx_msg void OnNcLButtonDown( UINT, CPoint )
ON_WM_NCLBUTTONUP( ) afx_msg void OnNcLButtonUp( UINT, CPoint )
ON_WM_NCMBUTTONDBLCLK( ) afx_msg void OnNcMButtonDblClk( UINT, CPoint )
ON_WM_NCMBUTTONDOWN( ) afx_msg void OnNcMButtonDown( UINT, CPoint )
ON_WM_NCMBUTTONUP( ) afx_msg void OnNcMButtonUp( UINT, CPoint )
ON_WM_NCMOUSEMOVE( ) afx_msg void OnNcMouseMove( UINT, CPoint )
ON_WM_NCPAINT( ) afx_msg void OnNcPaint( )
ON_WM_NCRBUTTONDBLCLK( ) afx_msg void OnNcRButtonDblClk( UINT, CPoint )
ON_WM_NCRBUTTONDOWN( ) afx_msg void OnNcRButtonDown( UINT, Cpoint )
ON_WM_NCRBUTTONUP( ) afx_msg void OnNcRButtonUp( UINT, CPoint ) P-R
ON_WM_PAINT( ) afx_msg void OnPaint( )
ON_WM_PAINTCLIPBOARD( ) afx_msg void OnPaintClipboard( CWnd*, HANDLE )
ON_WM_PALETTECHANGED( ) afx_msg void OnPaletteChanged( CWnd* )
ON_WM_PALETTEISCHANGING( ) afx_msg void OnPaletteIsChanging( CWnd* )
ON_WM_PARENTNOTIFY( ) afx_msg void OnParentNotify( UINT, LONG )
ON_WM_QUERYDRAGICON( ) afx_msg HCURSOR OnQueryDragIcon( )
ON_WM_QUERYENDSESSION( ) afx_msg BOOL OnQueryEndSession( )
ON_WM_QUERYNEWPALETTE( ) afx_msg BOOL OnQueryNewPalette( )
ON_WM_QUERYOPEN( ) afx_msg BOOL OnQueryOpen( )
ON_WM_RBUTTONDBLCLK( ) afx_msg void OnRButtonDblClk( UINT, CPoint )
ON_WM_RBUTTONDOWN( ) afx_msg void OnRButtonDown( UINT, CPoint )
ON_WM_RBUTTONUP( ) afx_msg void OnRButtonUp( UINT, CPoint )
ON_WM_RENDERALLFORMATS( ) afx_msg void OnRenderAllFormats( )
ON_WM_RENDERFORMAT( ) afx_msg void OnRenderFormat( UINT )
ON_WM_SETCURSOR( ) afx_msg BOOL OnSetCursor( CWnd*, UINT, UINT )
ON_WM_SETFOCUS( ) afx_msg void OnSetFocus( CWnd* )
ON_WM_SHOWWINDOW( ) afx_msg void OnShowWindow( BOOL, UINT )
ON_WM_SIZE( ) afx_msg void OnSize( UINT, int, int )
ON_WM_SIZECLIPBOARD( ) afx_msg void OnSizeClipboard( CWnd*, HANDLE )
ON_WM_SIZING( ) afx_msg void OnSizing( UINT, LPRECT )
ON_WM_SPOOLERSTATUS( ) afx_msg void OnSpoolerStatus( UINT, UINT )
ON_WM_STYLECHANGED( ) afx_msg void OnStyleChanged( int, LPSTYLESTRUCT )
ON_WM_STYLECHANGING( ) afx_msg void OnStyleChanging( int,LPSTYLESTRUCT )
ON_WM_SYSCHAR( ) afx_msg void OnSysChar( UINT, UINT, UINT )
ON_WM_SYSCOLORCHANGE( ) afx_msg void OnSysColorChange( )
ON_WM_SYSCOMMAND( ) afx_msg void OnSysCommand( UINT, LONG )
ON_WM_SYSDEADCHAR( ) afx_msg void OnSysDeadChar( UINT, UINT, UINT )
ON_WM_SYSKEYDOWN( ) afx_msg void OnSysKeyDown( UINT, UINT, UINT )
ON_WM_SYSKEYUP( ) afx_msg void OnSysKeyUp( UINT,UINT, UINT )
ON_WM_TCARD( ) afx_msg void OnTCard( UINT, DWORD )
ON_WM_TIMECHANGE( ) afx_msg void OnTimeChange( )
ON_WM_TIMER( ) afx_msg void OnTimer( UINT )
ON_WM_VKEYTOITEM( ) afx_msg int OnVKeyToItem( UINT, CWnd*, UINT )
ON_WM_VSCROLL( ) afx_msg void OnVScroll( UINT, UINT, CWnd* )
ON_WM_VSCROLLCLIPBOARD( ) afx_msg void OnVScrollClipboard( CWnd*, UINT, UINT )
ON_WM_WINDOWPOSCHANGED( ) afx_msg void OnWindowPosChanged( WINDOWPOS* lpwndpos )
ON_WM_WINDOWPOSCHANGING( ) afx_msg void OnWindowPosChanging( WINDOWPOS* lpwndpos )
ON_WM_WININICHANGE( ) afx_msg void OnWinIniChange( LPSTR )