Overriding Equals method in Structs

c# struct equals overriding
devoured elysium picture devoured elysium · Mar 30, 2010 · Viewed 31.2k times · Source

I've looked for overriding guidelines for structs, but all I can find is for classes.

At first I thought I wouldn't have to check to see if the passed object was null, as structs are value types and can't be null. But now that I come to think of it, as equals signature is

public bool Equals(object obj)

it seems there is nothing preventing the user of my struct to be trying to compare it with an arbitrary reference type.

My second point concerns the casting I (think I) have to make before I compare my private fields in my struct. How am I supposed to cast the object to my struct's type? C#'s as keyword seems only suitable for reference types.

Answer

James Curran picture James Curran · Mar 30, 2010 
struct MyStruct 
{
   public override bool Equals(object obj) 
   {
       if (!(obj is MyStruct))
          return false;

       MyStruct mys = (MyStruct) obj;
       // compare elements here

   }

}

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