That Is, you can create your own definition of structural equality and specify that this definition be used with a collection type that accepts the IStructuralEquatable interface. = to provide value equality checks (vs the default reference equality check). The MSDN documentation suggests you only do it for immutable types. https://cobjectkullanm30517.ampedpages.com/you-should-know-c-istructuralequatable-temel-Özellikleri-göstergeleri-55548194