//【例3.0】顯示一個消息框。

#include <afxwin.h>
class CEx3_0App: public CWinApp{
	public:
		virtual BOOL InitInstance(){
		    MessageBox(NULL,"Simplest MFC  Application.","Ex3_0",MB_OK);
			return TRUE;
		}
	};
CEx3_0App theApp; //全局變量，代表應用程序本身。