该程序需要实现四个功能：添加，删除，修改，查找。

添加：分为往listview里的添加和txt里的添加。

删除：listview中的删除可用remove函数，文件中的删除，需要读取文件中的所有信息，然后进行对比，当不同时写入文件，相同跳过，然后删除原文件。

修改：和删除类似。

-The program needs to achieve four functions: add, delete, modify, search.

Added: divided and added to the listview in txt Lane added.

Delete: listview available remove the delete function to delete a file, you need to read all the information in the file, and then compare, if not simultaneously written to the file, the same as skipping, and then delete the original file.

Review: and delete similar.