本程序演示一个用 mid 窗口实现的编辑器，并能防止打开多个实例-a demonstration of the process used to achieve the mid window editor, and can prevent a number of examples of open

本程序演示一个用 mid 窗口实现的编辑器，并能防止打开多个实例-a demonstration of the process used to achieve the mid window editor, and can prevent a number of examples of open