#408 – Overloading the == Operator for a Reference Type

You can override the Equals method for a type to implement value equality for the type. You can also overload the == operator.

By default, the == operator will do a reference equality check, only returning true if two references point to exactly the same object.  This is normally what you want for a reference type, using the Equals method if you want to check for value equality.  But there might be cases when you want to also overload the == operator, having it also check for value equality.  You might do this if your type represents some basic value, like a complex number.

Some guidelines.  Whenever you overload the == operator, you should also:

  • Overload != operator
  • Override Equals method
  • Overload < and > operators
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About Sean
Software developer in the Twin Cities area, passionate about software development and sailing.

2 Responses to #408 – Overloading the == Operator for a Reference Type

  1. Pingback: #412 – Guidelines when Overloading == Operator for a Value Type « 2,000 Things You Should Know About C#

  2. Pingback: #1,141 – Reference Equality Used Even when Overload Available for Typed Parameter | 2,000 Things You Should Know About C#

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