看到代碼里有用位操作來判斷條件的，以前沒有這么用過，做個筆記:

int add = 2;int modify = 4;int delete = 8;Console.WriteLine((add | modify | delete) & add); //2Console.WriteLine((add | modify | delete) & modify); //4Console.WriteLine((add | modify | delete) & delete); //8

但是直接使用整數進行位操作，可讀性不太好。

其實C#里有枚舉，也可以實現，但是C#的枚舉可讀性應該更好

[Flags]enum OperatingAuthorization{    Add = 2,    Modify = 4,    Delete = 8}OperatingAuthorization allOperating = OperatingAuthorization.Add | OperatingAuthorization.Modify | OperatingAuthorization.Delete;Console.WriteLine(allOperating & OperatingAuthorization.Add); //Add

這個可以用于判斷權限是否存在，
如allOperating & OperatingAuthorization.Add == OperatingAuthorization.Add，則可確定allOperating包含OperatingAuthorization.Add
這里可以假定allOperating是從數據庫取出來的