一个SDI(单文档界面)的应用，通过File菜单中的Create New Frame命令能够创建一个位于顶层的SDI应用，但关闭主应用后其它的窗口也将关闭，程序由Visual C++ 5.0开发-an SDI (single-document interface) applications, through the File menu on the Create New Frame order to create one at the top of SDI applications, but closed after the other main application window will be closed and procedures developed in Visual C 5.0