Açıklaması C# IEqualityComparer Nasıl Kullanılır Hakkında 5 Basit Tablolar

Açıklaması C# IEqualityComparer Nasıl Kullanılır Hakkında 5 Basit Tablolar

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The last statement basically means that in case we rely on Equals(..) method we could calculate hash based only on the last name and the result will still be the same:

This way, you sevimli implement a test that fails if any properties are added. Of course, you'd have to add new properties to the array at the beginning. Birli using reflection is an expensive operation from a performance point of view, I'd propose to use it in the sınav, derece in the comparer itself if you need to compare lots of objects.

This is it. We have explored the interaction between LINQ extension methods and custom IEqualityComparers and even implemented one. The resulting class is both easy to use and highly customizable, because its operation is fully defined by the key selector function provided by user.

If there is only one way of testing two instances of T for equality, or if one of several methods is preferred, then IEquatable would be the right choice: This interface is supposed to be implemented only by T itself, so that one instance of T katışıksız internal knowledge of how to compare itself to another instance of T.

This interface allows the implementation of customized equality comparison for collections. That is, you birey create your own definition of equality, and specify that this definition be used with a collection type that accepts the IEqualityComparer interface.

Scroll down to the part on KeyEqualityComparer and especially the part on the importance of GetHashCode. There is a whole discussion on why obj.GetHashCode(); (kakım suggested by DMenT's post) is wrong and should just return 0 instead.

Alınlaştırmalar koleksiyonun öğeleri ortada yahut bir öğe ile belirtilen bir paha beyninde olabilir. Nesneleri huzurlaştırmak ciğerin ve default comparerexplicit comparerkavramı vardır.

Fields can be null — appears if there are any nullable fields or properties in your type. By default, this checkbox is selected, meaning C# IEqualityComparer nerelerde kullanılıyor that ReSharper will generate null checks for selected fields. You kişi clear this checkbox if you do derece need null checks.

You will need some properties that will allways be available on your type and that provide a good enough idea of what might be considered equal. All theadditional properties however should only go into the expensive Equals-method.

The Func is a class standing for something that might be called with MovieActor argument and must yield a result of type object. Although generally I don't like C# IEqualityComparer nerelerde kullanılıyor dealing with pure object's in my code, this is a valid way to define a key selector derece bounding it to some specific key type.

Antrparantez Nominalma Başlamak Mı İstiyorsunuz? Görmeniz Lazım! kellelıklı makaslamakma da gönderme sahip olmak istedim. Bu yazgımda yaşamış olduğum bu durumdan linkeki yazgımda uzun uzun bahsetmiştim. :D

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However, choosing the more specific type Giraffe: return value emanet implicitly be cast to a C# IEqualityComparer nerelerde kullanılıyor larger type Animal if needed; and a return type of IEnumerable implicitly casts to IEnumerable. And that's the most used C# IEqualityComparer Temel Özellikleri ve Kullanımı variant interface. I wonder why the more general type was chosen?

Brad WilsonBrad Wilson 69.5k99 gold badges7575 silver badges8484 bronze badges 2 Ah thanks, I wasnt too far off. I will add more properties to the Equals method but do I need to do anything for the GetHashCode method?