修改删书操作
修改User中错误
修改某郭的错误
修改
Merge branch 'master' of https://winupsoftware.visualstudio.com/defaultcollection/_git/Library%20Management%20System
又修改
提交
Merge branch 'master' of https://winupsoftware.visualstudio.com/defaultcollection/_git/Library%20Management%20System
细节修改