struct AFX_MSGMAP_ENTRY
{
 unsigned int nMessage;   // windows消息
 unsigned int nCode;      // control code or WM_NOTIFY code
 unsigned int nID;        // control ID (or 0 for windows messages)
 unsigned int nLastID;    // used for entries specifying a range of control id's
 unsigned int nSig;       // signature type (action) or pointer to message #
 void* pfn;     // routine to call (or special value)
};

struct AFX_MSGMAP
{
 const AFX_MSGMAP* pBaseMap;
 const AFX_MSGMAP_ENTRY* lpEntries;
};

//DECLARE_MESSAGE_MAP()
private:
 static const AFX_MSGMAP_ENTRY _messageEntries[];
protected:
 static  const AFX_MSGMAP    messageMap;
 static  const AFX_MSGMAP*   _GetBaseMessageMap();
 virtual const AFX_MSGMAP*   GetMessageMap() const;