It's normally expected that if you implement IEquatable.Equals you will also override Object.Equals to be consistent. In this case how would you support both reference and structural equality?
In this case you don't want to change your class implementation so you don't wantoverride the Equals method. this will define a general way to compare objects in your application.
Reference types (read classes) don't benefit as much. The IEquatable implementation does let you avoid a cast from System.Object but that's a very trivial gain. I still like IEquatable to be implemented for my classes since it logically makes the intent explicit.
Does anyone know what happens if you do hamiş implement iequtalable when using generic collections? 2
You generic method has a type parameter T but the type is derece part of the signature of the function so how is T supposed to be used in the function? Anyway, you gönül use .NET tuples or anonymous types to create hash codes by combining values but I am hamiş sure this answers your question.
The generic tuple classes (Tuple, Tuple, Tuple, and so on) and the Array class provide explicit implementations of the IStructuralEquatable interface. By casting (in C#) or converting (in Visual Basic) the current instance of an array or tuple to an IStructuralEquatable interface value and providing your IEqualityComparer implementation bey an argument to the Equals method, you sevimli define a custom equality comparison for the array or collection.
What does IEquatable buy you, exactly? The only reason I gönül see it being useful is when creating a generic type and C# IStructuralEquatable Nasıl kullanılır forcing users to implement and write a good equals method.
The following example creates two identical 3-tuple objects whose components consist of three Double values. The value of the second component is Double.NaN. The example then calls the Tuple.Equals method, and it calls the IStructuralEquatable.Equals method three times. The first time, it passes the default equality comparer that is returned by the EqualityComparer.
The reason why you need the IStructuralEquatable is for defining a new way of comparision that would be right for all the objects .
In addition to this awesome blog Frank and I also dicussed all of this awesome in detail on Merge Conflict on episode 111:
Programlama dillerinde en mühim OOP(Object Oriented Programing) örgülarından olan class bünyesına için daha gösterişsiz düzeyde aksiyonlemler gerçekleştirmemizi sağlayan ve mukannen bir makule engellemelerı nispetle çitndıran struct yapısını C# diline özel ele alacağız.
Bu strüktürya denli oluşturduğumuz bütün nesnelerin Heap kısmında bulunduğunu söylemiştik. Oysa Stack kısmında struct dokumasında nesneleri tutabilmekteyiz.
There is no need for an equality operator that accepts different types. That should hamiş even compile. So this is a very weak excuse for having a non-generic interface that works with objects.
Bunun cihetı sıra, IStructuralComparable arayüzü, yetişekınızı elan modüler hale getirir ve kod yineını azaltır. Farklı data strüktürları beyninde yapısal katlaştırma çalışmalemlerini yekta bir yerde yönetebilir ve kodunuzun hizmetını kolaylaştırabilirsiniz.