MFC的CFrameWnd::OnCmdMsg消息链路

首先是视图类，其次是窗口类，然后是应用程序类。下面的源码为证。

BOOL CFrameWnd::OnCmdMsg(UINT nID, int nCode, void* pExtra,
 AFX_CMDHANDLERINFO* pHandlerInfo)
{
 CPushRoutingFrame push(this);

 // pump through current view FIRST
 CView* pView = GetActiveView();
 if (pView != NULL && pView->OnCmdMsg(nID, nCode, pExtra, pHandlerInfo))
  return TRUE;

 // then pump through frame
 if (CWnd::OnCmdMsg(nID, nCode, pExtra, pHandlerInfo))
  return TRUE;

 // last but not least, pump through app
 CWinApp* pApp = AfxGetApp();
 if (pApp != NULL && pApp->OnCmdMsg(nID, nCode, pExtra, pHandlerInfo))
  return TRUE;

 return FALSE;
}