为了实现文件传输功能，特整理了一下有关读取指定文件下其子目录信息的读取方法，及添加双击事件循环读取下一层信息的功能。

-In order to achieve the file transfer function, special order a bit about reading the specified file to read the information under the method of its subdirectories, and added double-click the event loop reads the next level of information functions.