Item 6: Understand the Relationships Among the Many Different Concepts of Equality(Effective C#)

　　C# gives you numerous ways to test equality, but you need to consider providing your own definitions for only two of them, along with supporting the analogous interfaces. You never override the static Object.ReferenceEquals() and static Object.Equals() because they provide the correct tests, regardless of the runtime type. You always override instance Equals() and operator==() for value types to provide better performance. You override instance Equals() for reference types when you want equality to mean something other than object identity.

转载于:https://www.cnblogs.com/zhtf2014/archive/2011/01/12/1934030.html