Implementing IEquatable is not enough to use a class as a Dictionary key

Note to future self: it is not enough to implement IEquatable<T> to use a class as a Dictionary key.

Today I needed a Dictionary with a composite key, a combination of several values. So I quickly cooked up a class with public properties to cover the values and for ease of use, a constructor to quickly set those values. But to be able to use it as a dictionary key, I would need a little more. Per default, classes are only checked for reference equality, which makes sense. But I would need to have the system evaluate two separate instances of this class as equal, if all of their properties were equal. Lees meer over dit bericht