以递归搜索的方法实现对目录的遍历,然后用treeview现实整个目录树.-recursive search for the right way to achieve directory traversal, and then use the treeview reality the whole directory tree.

打开windows中资源管理器目录，搜索节点，能够只打开所有文件中的图片。-Open the windows directory of the Explorer, the search node can not just open all the files in the picture.