MFC消息机制一

消息映射值集合

enum AfxSig{AfxSig_end = 0,     // [marks end of message map]AfxSig_bD,      // BOOL (CDC*)AfxSig_bb,      // BOOL (BOOL)AfxSig_bWww,    // BOOL (CWnd*, UINT, UINT)AfxSig_hDWw,    // HBRUSH (CDC*, CWnd*, UINT)AfxSig_hDw,     // HBRUSH (CDC*, UINT)AfxSig_iwWw,    // int (UINT, CWnd*, UINT)AfxSig_iww,     // int (UINT, UINT)AfxSig_iWww,    // int (CWnd*, UINT, UINT)AfxSig_is,      // int (LPTSTR)AfxSig_lwl,     // LRESULT (WPARAM, LPARAM)AfxSig_lwwM,    // LRESULT (UINT, UINT, CMenu*)AfxSig_vv,      // void (void)AfxSig_vw,      // void (UINT)AfxSig_vww,     // void (UINT, UINT)AfxSig_vvii,    // void (int, int) // wParam is ignoredAfxSig_vwww,    // void (UINT, UINT, UINT)AfxSig_vwii,    // void (UINT, int, int)AfxSig_vwl,     // void (UINT, LPARAM)AfxSig_vbWW,    // void (BOOL, CWnd*, CWnd*)AfxSig_vD,      // void (CDC*)AfxSig_vM,      // void (CMenu*)AfxSig_vMwb,    // void (CMenu*, UINT, BOOL)AfxSig_vW,      // void (CWnd*)AfxSig_vWww,    // void (CWnd*, UINT, UINT)AfxSig_vWp,     // void (CWnd*, CPoint)AfxSig_vWh,     // void (CWnd*, HANDLE)AfxSig_vwW,     // void (UINT, CWnd*)AfxSig_vwWb,    // void (UINT, CWnd*, BOOL)AfxSig_vwwW,    // void (UINT, UINT, CWnd*)AfxSig_vwwx,    // void (UINT, UINT)AfxSig_vs,      // void (LPTSTR)AfxSig_vOWNER,  // void (int, LPTSTR), force return TRUEAfxSig_iis,     // int (int, LPTSTR)AfxSig_wp,      // UINT (CPoint)AfxSig_wv,      // UINT (void)AfxSig_vPOS,    // void (WINDOWPOS*)AfxSig_vCALC,   // void (BOOL, NCCALCSIZE_PARAMS*)AfxSig_vNMHDRpl,    // void (NMHDR*, LRESULT*)AfxSig_bNMHDRpl,    // BOOL (NMHDR*, LRESULT*)AfxSig_vwNMHDRpl,   // void (UINT, NMHDR*, LRESULT*)AfxSig_bwNMHDRpl,   // BOOL (UINT, NMHDR*, LRESULT*)AfxSig_bHELPINFO,   // BOOL (HELPINFO*)AfxSig_vwSIZING,    // void (UINT, LPRECT) -- return TRUE// signatures specific to CCmdTargetAfxSig_cmdui,   // void (CCmdUI*)AfxSig_cmduiw,  // void (CCmdUI*, UINT)AfxSig_vpv,     // void (void*)AfxSig_bpv,     // BOOL (void*)// Other aliases (based on implementation)AfxSig_vwwh,                // void (UINT, UINT, HANDLE)AfxSig_vwp,                 // void (UINT, CPoint)AfxSig_bw = AfxSig_bb,      // BOOL (UINT)AfxSig_bh = AfxSig_bb,      // BOOL (HANDLE)AfxSig_iw = AfxSig_bb,      // int (UINT)AfxSig_ww = AfxSig_bb,      // UINT (UINT)AfxSig_bv = AfxSig_wv,      // BOOL (void)AfxSig_hv = AfxSig_wv,      // HANDLE (void)AfxSig_vb = AfxSig_vw,      // void (BOOL)AfxSig_vbh = AfxSig_vww,    // void (BOOL, HANDLE)AfxSig_vbw = AfxSig_vww,    // void (BOOL, UINT)AfxSig_vhh = AfxSig_vww,    // void (HANDLE, HANDLE)AfxSig_vh = AfxSig_vw,      // void (HANDLE)AfxSig_viSS = AfxSig_vwl,   // void (int, STYLESTRUCT*)AfxSig_bwl = AfxSig_lwl,AfxSig_vwMOVING = AfxSig_vwSIZING,  // void (UINT, LPRECT) -- return TRUEAfxSig_vW2,                 // void (CWnd*) (CWnd* comes from lParam)AfxSig_bWCDS,               // BOOL (CWnd*, COPYDATASTRUCT*)AfxSig_bwsp,                // BOOL (UINT, short, CPoint)AfxSig_vws,};

上面的这些值会在CMDTARG.CPP 文件中的_AfxDispatchCmdMsg（）函数中用到

AFX_STATIC BOOL AFXAPI _AfxDispatchCmdMsg(CCmdTarget* pTarget, UINT nID, int nCode,AFX_PMSG pfn, void* pExtra, UINT nSig, AFX_CMDHANDLERINFO* pHandlerInfo)// return TRUE to stop routing{ASSERT_VALID(pTarget);UNUSED(nCode);   // unused in release buildsunion MessageMapFunctions mmf;mmf.pfn = pfn;BOOL bResult = TRUE; // default is okif (pHandlerInfo != NULL){// just fill in the information, don't do itpHandlerInfo->pTarget = pTarget;pHandlerInfo->pmf = mmf.pfn;return TRUE;}switch (nSig){case AfxSig_vv:// normal command or control notificationASSERT(CN_COMMAND == 0);        // CN_COMMAND same as BN_CLICKEDASSERT(pExtra == NULL);(pTarget->*mmf.pfn_COMMAND)();break;case AfxSig_bv:// normal command or control notificationASSERT(CN_COMMAND == 0);        // CN_COMMAND same as BN_CLICKEDASSERT(pExtra == NULL);bResult = (pTarget->*mmf.pfn_bCOMMAND)();break;case AfxSig_vw:// normal command or control notification in a rangeASSERT(CN_COMMAND == 0);        // CN_COMMAND same as BN_CLICKEDASSERT(pExtra == NULL);(pTarget->*mmf.pfn_COMMAND_RANGE)(nID);break;case AfxSig_bw:// extended command (passed ID, returns bContinue)ASSERT(pExtra == NULL);bResult = (pTarget->*mmf.pfn_COMMAND_EX)(nID);break;case AfxSig_vNMHDRpl:{AFX_NOTIFY* pNotify = (AFX_NOTIFY*)pExtra;ASSERT(pNotify != NULL);ASSERT(pNotify->pResult != NULL);ASSERT(pNotify->pNMHDR != NULL);(pTarget->*mmf.pfn_NOTIFY)(pNotify->pNMHDR, pNotify->pResult);}break;case AfxSig_bNMHDRpl:{AFX_NOTIFY* pNotify = (AFX_NOTIFY*)pExtra;ASSERT(pNotify != NULL);ASSERT(pNotify->pResult != NULL);ASSERT(pNotify->pNMHDR != NULL);bResult = (pTarget->*mmf.pfn_bNOTIFY)(pNotify->pNMHDR, pNotify->pResult);}break;case AfxSig_vwNMHDRpl:{AFX_NOTIFY* pNotify = (AFX_NOTIFY*)pExtra;ASSERT(pNotify != NULL);ASSERT(pNotify->pResult != NULL);ASSERT(pNotify->pNMHDR != NULL);(pTarget->*mmf.pfn_NOTIFY_RANGE)(nID, pNotify->pNMHDR,pNotify->pResult);}break;case AfxSig_bwNMHDRpl:{AFX_NOTIFY* pNotify = (AFX_NOTIFY*)pExtra;ASSERT(pNotify != NULL);ASSERT(pNotify->pResult != NULL);ASSERT(pNotify->pNMHDR != NULL);bResult = (pTarget->*mmf.pfn_NOTIFY_EX)(nID, pNotify->pNMHDR,pNotify->pResult);}break;case AfxSig_cmdui:{// ON_UPDATE_COMMAND_UI or ON_UPDATE_COMMAND_UI_REFLECT caseASSERT(CN_UPDATE_COMMAND_UI == (UINT)-1);ASSERT(nCode == CN_UPDATE_COMMAND_UI || nCode == 0xFFFF);ASSERT(pExtra != NULL);CCmdUI* pCmdUI = (CCmdUI*)pExtra;ASSERT(!pCmdUI->m_bContinueRouting);    // idle - not set(pTarget->*mmf.pfn_UPDATE_COMMAND_UI)(pCmdUI);bResult = !pCmdUI->m_bContinueRouting;pCmdUI->m_bContinueRouting = FALSE;     // go back to idle}break;case AfxSig_cmduiw:{// ON_UPDATE_COMMAND_UI caseASSERT(nCode == CN_UPDATE_COMMAND_UI);ASSERT(pExtra != NULL);CCmdUI* pCmdUI = (CCmdUI*)pExtra;ASSERT(pCmdUI->m_nID == nID);           // sanity assertASSERT(!pCmdUI->m_bContinueRouting);    // idle - not set(pTarget->*mmf.pfn_UPDATE_COMMAND_UI_RANGE)(pCmdUI, nID);bResult = !pCmdUI->m_bContinueRouting;pCmdUI->m_bContinueRouting = FALSE;     // go back to idle}break;// general extensibility hookscase AfxSig_vpv:(pTarget->*mmf.pfn_OTHER)(pExtra);break;case AfxSig_bpv:bResult = (pTarget->*mmf.pfn_OTHER_EX)(pExtra);break;default:    // illegalASSERT(FALSE);return 0;}return bResult;}

但是注意：上面的函数中会出现MessageMapFunctions这么一个枚举类型的结构体型结构，一般F12是定位不到他的定义的，其实他是在AFXIMPL.H 文件中定义的

MessageMapFunctions结构体中实际上定义的是一些函数的指针

union MessageMapFunctions{AFX_PMSG pfn;   // generic member function pointer// specific type safe variants for WM_COMMAND and WM_NOTIFY messagesvoid (AFX_MSG_CALL CCmdTarget::*pfn_COMMAND)();BOOL (AFX_MSG_CALL CCmdTarget::*pfn_bCOMMAND)();void (AFX_MSG_CALL CCmdTarget::*pfn_COMMAND_RANGE)(UINT);BOOL (AFX_MSG_CALL CCmdTarget::*pfn_COMMAND_EX)(UINT);void (AFX_MSG_CALL CCmdTarget::*pfn_UPDATE_COMMAND_UI)(CCmdUI*);void (AFX_MSG_CALL CCmdTarget::*pfn_UPDATE_COMMAND_UI_RANGE)(CCmdUI*, UINT);void (AFX_MSG_CALL CCmdTarget::*pfn_OTHER)(void*);BOOL (AFX_MSG_CALL CCmdTarget::*pfn_OTHER_EX)(void*);void (AFX_MSG_CALL CCmdTarget::*pfn_NOTIFY)(NMHDR*, LRESULT*);BOOL (AFX_MSG_CALL CCmdTarget::*pfn_bNOTIFY)(NMHDR*, LRESULT*);void (AFX_MSG_CALL CCmdTarget::*pfn_NOTIFY_RANGE)(UINT, NMHDR*, LRESULT*);BOOL (AFX_MSG_CALL CCmdTarget::*pfn_NOTIFY_EX)(UINT, NMHDR*, LRESULT*);// type safe variant for thread messagesvoid (AFX_MSG_CALL CWinThread::*pfn_THREAD)(WPARAM, LPARAM);// specific type safe variants for WM-style messagesBOOL    (AFX_MSG_CALL CWnd::*pfn_bD)(CDC*);BOOL    (AFX_MSG_CALL CWnd::*pfn_bb)(BOOL);BOOL    (AFX_MSG_CALL CWnd::*pfn_bWww)(CWnd*, UINT, UINT);BOOL    (AFX_MSG_CALL CWnd::*pfn_bHELPINFO)(HELPINFO*);BOOL    (AFX_MSG_CALL CWnd::*pfn_bWCDS)(CWnd*, COPYDATASTRUCT*);HBRUSH  (AFX_MSG_CALL CWnd::*pfn_hDWw)(CDC*, CWnd*, UINT);HBRUSH  (AFX_MSG_CALL CWnd::*pfn_hDw)(CDC*, UINT);int     (AFX_MSG_CALL CWnd::*pfn_iwWw)(UINT, CWnd*, UINT);int     (AFX_MSG_CALL CWnd::*pfn_iww)(UINT, UINT);int     (AFX_MSG_CALL CWnd::*pfn_iWww)(CWnd*, UINT, UINT);int     (AFX_MSG_CALL CWnd::*pfn_is)(LPTSTR);LRESULT (AFX_MSG_CALL CWnd::*pfn_lwl)(WPARAM, LPARAM);LRESULT (AFX_MSG_CALL CWnd::*pfn_lwwM)(UINT, UINT, CMenu*);void    (AFX_MSG_CALL CWnd::*pfn_vv)(void);void    (AFX_MSG_CALL CWnd::*pfn_vw)(UINT);void    (AFX_MSG_CALL CWnd::*pfn_vww)(UINT, UINT);void    (AFX_MSG_CALL CWnd::*pfn_vvii)(int, int);void    (AFX_MSG_CALL CWnd::*pfn_vwww)(UINT, UINT, UINT);void    (AFX_MSG_CALL CWnd::*pfn_vwii)(UINT, int, int);void    (AFX_MSG_CALL CWnd::*pfn_vwl)(WPARAM, LPARAM);void    (AFX_MSG_CALL CWnd::*pfn_vbWW)(BOOL, CWnd*, CWnd*);void    (AFX_MSG_CALL CWnd::*pfn_vD)(CDC*);void    (AFX_MSG_CALL CWnd::*pfn_vM)(CMenu*);void    (AFX_MSG_CALL CWnd::*pfn_vMwb)(CMenu*, UINT, BOOL);void    (AFX_MSG_CALL CWnd::*pfn_vW)(CWnd*);void    (AFX_MSG_CALL CWnd::*pfn_vWww)(CWnd*, UINT, UINT);void    (AFX_MSG_CALL CWnd::*pfn_vWp)(CWnd*, CPoint);void    (AFX_MSG_CALL CWnd::*pfn_vWh)(CWnd*, HANDLE);void    (AFX_MSG_CALL CWnd::*pfn_vwW)(UINT, CWnd*);void    (AFX_MSG_CALL CWnd::*pfn_vwWb)(UINT, CWnd*, BOOL);void    (AFX_MSG_CALL CWnd::*pfn_vwwW)(UINT, UINT, CWnd*);void    (AFX_MSG_CALL CWnd::*pfn_vwwx)(UINT, UINT);void    (AFX_MSG_CALL CWnd::*pfn_vs)(LPTSTR);void    (AFX_MSG_CALL CWnd::*pfn_vOWNER)(int, LPTSTR);   // force return TRUEint     (AFX_MSG_CALL CWnd::*pfn_iis)(int, LPTSTR);UINT    (AFX_MSG_CALL CWnd::*pfn_wp)(CPoint);UINT    (AFX_MSG_CALL CWnd::*pfn_wv)(void);void    (AFX_MSG_CALL CWnd::*pfn_vPOS)(WINDOWPOS*);void    (AFX_MSG_CALL CWnd::*pfn_vCALC)(BOOL, NCCALCSIZE_PARAMS*);void    (AFX_MSG_CALL CWnd::*pfn_vwp)(UINT, CPoint);void    (AFX_MSG_CALL CWnd::*pfn_vwwh)(UINT, UINT, HANDLE);BOOL    (AFX_MSG_CALL CWnd::*pfn_bwsp)(UINT, short, CPoint);void    (AFX_MSG_CALL CWnd::*pfn_vws)(UINT, LPCTSTR);};

其中AFX_PMSG这个结构的定义是在AFXWIN.H 文件中定义的

typedef void (AFX_MSG_CALL CCmdTarget::*AFX_PMSG)(void);

通过以上的这些数据和函数MFC把其内部凌乱的流程函数全部都进行了整理、汇总；但是请注意：_AfxDispatchCmdMsg虽然是一个MFC的全局函数但是MessageMapFunctions结构中的函数指针所指向的大多数都是CCmdTarget类中的函数，可见CCmdTarget类对前期流程控制的重要性