创建一个窗口、了解其他的 M F C类、把消息 发送到一个窗口和在一个窗口内绘图。当然还有其他一些基本知识，我们也将在涉及时适当 地进行讨论-Create a window to understand the other MFC classes, the message sent to a window and a window in the drawing. Of course there are other basic knowledge, we will also be invol