c# - What's the difference between IEquatable and just overriding Object.Equals()? -

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i want food class able test whenever equal instance of food. later use against list, , want use list.contains() method. should implement iequatable<food> or override object.equals()? msdn:

this method determines equality using default equality comparer, defined object's implementation of iequatable.equals method t (the type of values in list).

so next question is: functions/classes of .net framework make use of object.equals()? should use in first place?

the main reason performance. when generics introduced in .net 2.0 able add bunch of neat classes such list<t>, dictionary<k,v>, hashset<t>, etc. these structures make heavy use of gethashcode , equals. value types required boxing. iequatable<t> lets structure implement typed equals method no boxing required. better performance when using value types generic collections.

reference types don't benefit iequatable<t> implementation let avoid cast system.object can make difference if it's called frequently.

as noted on jared parson's blog though, still must implement object overrides.


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