Question

While implementing an == operator, I have the feeling that I am missing some essential points.
Hence, I am searching some best practices around that.
Here are some related questions I am thinking about:

• How to cleanly handle the reference comparison?
• Should it be implemented through a IEquatable<T>-like interface? Or overriding object.Equals?
• And what about the != operator?

(this list might not be exhaustive).

Answer 1

I would follow Microsoft’s Guidelines for Overloading Equals() and Operator ==.

edit: Microsoft’s guidelines contain this important remark, which seems to confirm Henk’s answer:

By default, the operator == tests for reference equality by
determining if two references indicate the same object, so reference
types do not need to implement operator == in order to gain this
functionality. When a type is immutable, meaning the data contained in
the instance cannot be changed, overloading operator == to compare
value equality instead of reference equality can be useful because, as
immutable objects, they can be considered the same as long as they
have the same value. Overriding operator == in non-immutable types is
not recommended