DECLARE_MESSAGE_MAP

DECLARE_MESSAGE_MAP(): Declares that the class defines a message map. Each CCmdTarget-derived class in your program must provide a message map to handle messages.

Use the
DECLARE_MESSAGE_MAP macro at the
end of your class declaration. Then, in the
.cpp file that defines the member functions for the class, use the BEGIN_MESSAGE_MAP
macro, macro entries for each of your message-handler functions, and the
END_MESSAGE_MAP macro.

If you declare any member
after
DECLARE_MESSAGE_MAP, you must
specify a new access type (public, private, or protected) for them.

BEGIN_MESSAGE_MAP(theClass, baseClass), END_MESSAGE_MAP()

在类定义的末尾添加DECLARE_MESSAGE_MAP 宏。在.CPP文件中定义类的成员函数：在消息处理函数的入口处添加BEGIN_MESSAGE_MAP(theClass,
baseClass), 在消息处理函数的尾部添加END_MESSAGE_MAP()。

如果在DECLARE_MESSAGE_MAP
后面添加任何成员，那么你必须为它们定义一个新的类型（公共，私有，或者保护），这句话说明了DECLARE_MESSAGE_MAP的位置不是固定的。