mfc的宏

#define BEGIN_MESSAGE_MAP(theClass, baseClass) \
const AFX_MSGMAP* PASCAL theClass::_GetBaseMessageMap() \
{ return &baseClass::messageMap; } \
const AFX_MSGMAP* theClass::GetMessageMap() const \
{ return &theClass::messageMap; } \
AFX_COMDAT AFX_DATADEF const AFX_MSGMAP theClass::messageMap = \
{ &theClass::_GetBaseMessageMap, &theClass::_messageEntries[0] }; \
AFX_COMDAT const AFX_MSGMAP_ENTRY theClass::_messageEntries[] = \
{ \

#else
#define BEGIN_MESSAGE_MAP(theClass, baseClass) \
const AFX_MSGMAP* theClass::GetMessageMap() const \
{ return &theClass::messageMap; } \
AFX_COMDAT AFX_DATADEF const AFX_MSGMAP theClass::messageMap = \
{ &baseClass::messageMap, &theClass::_messageEntries[0] }; \
AFX_COMDAT const AFX_MSGMAP_ENTRY theClass::_messageEntries[] = \
{ \

#endif

#define END_MESSAGE_MAP() \
{0, 0, 0, 0, AfxSig_end, (AFX_PMSG)0 } \
}; \
大家能给我说一说 6这段代码吗 或者 给我 推荐什么资料的 ，我 是新手 实在看不懂 这段代码