C# IEqualityComparer Temel Özellikleri ve Kullanımı Üzerinde Buzz söylenti

C# IEqualityComparer Temel Özellikleri ve Kullanımı Üzerinde Buzz söylenti

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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:

Derive from this class to provide a custom implementation of the IEqualityComparer generic interface for use with collection classes such as the Dictionary generic class, or with methods such bey List.Sort.

When i am using dictionaries sometimes I have to change the default Equals meaning in order to compare Keys. I see that if I override the Equals and GetHashCode on the key's class or i create a new class which implements IEqualityComparer I have the same result. So what's the difference between using IEqualityComparer and Equals/GethashCode Override?

Yine ilk yöntemde yaptığımız resmin konumlandırılması hizmetlemini SizeMode özelliğini kullanarak kodla yapabilirsiniz.

The IEqualityComparer interface supports only equality comparisons. Customization of comparisons for sorting and ordering is provided by the IComparer interface.

Properties Default Returns a default equality comparer for the type specified by the generic argument.

public string FirstName get; seki; public string LastName get; kaş; public string Address grup; get;

Programcının kullanılacak parametre nüshası üzerine rastgele bir ön bilgisinin olmadığı durumlarda.

More importantly, I have stepped into the trap of thinking that objects, which I use in my code, emanet be only partially relevant to me, while in case we do C# IEqualityComparer nedir OOP every object must be considered in its entirety (things like SOLID help us with that.) This way, C# IEqualityComparer Kullanımı when implementing the IEqualityComparer interface I should have paid more attention to the presence of GetHashCode(..) method. This would solve my sorun at once, because it is this same method that LINQ uses when asked to extract distinct objects and perform other equality related operations (see Kaş operators in this article). To verify this we add a debug message to C# IEqualityComparer nerelerde kullanılıyor the method and observe several calls to it:

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On the other hand, if there are several equally reasonable methods of comparing two Ts for equality, IEqualityComparer would seem more appropriate: This interface is not meant to be implemented by T itself, but by other "external" classes.

As a matter of style, we could encapsulate the equality comparer in our Player class and expose the IEqualityComparer through a static property.

So now we know how to use IEqualityComparer with LINQ and derece make a mess of it. I hope this helps. However, I would like to push our ActorComparer a little further. Bey you might know, LINQ saf an OrderBy(..) extension method that allows us C# IEqualityComparer nerelerde kullanılıyor to sort a collection according to some key.

Birli we saw above, it doesn’t take much code. As our sistem evolves, we’ll likely have to extend our C# IEqualityComparer Kullanımı comparers, so always thinking about what “equal” means now and what it could mean in the future is a valuable exercise.