C# IEqualityComparer Temel Özellikleri ve Kullanımı Temel Açıklaması

C# IEqualityComparer Temel Özellikleri ve Kullanımı Temel Açıklaması

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Burada enum kümesinde olmayan bir elemana erişmek isteriz. Runtime da hiç bir sorun olmaz ve bize sayısal kıymeti veya olması müstelzim numerik değeri döner , teltik bulunduğunun ayırtına varmayız. Yeniden bile denetçi etmekte fayda var :)

This transformation allows for faster comparison of elements during look-up, because the elements of the second kaş are easier to compare and because there are fewer of them. Still, due to this same reason any hash function might eventually produce equal codes for non equal objects

The CompareTo method would be the default way of ordering your User class, perhaps comparing by Name. If you then decided that you wanted to sort a list of User objects by another property, say Age, you could write a class that implemented IComparer instead of altering CompareTo inside User. This would perform the custom sorting, for example:

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

The comparer will validate that prop1 is the same (and add B to the pool), then validate that prop2 is the same (and add C to the pool), and when it validates prop3, even though they're different, since both B and C are in the pool, the comparer will consider them C# IEqualityComparer Kullanımı to be the same.

This meant that your client now needs to retrieve and then process a larger number of records, which will always be less efficient that performing the lookup on the database where the approprate indexes sevimli be used.

You could possibly create a GenericComparer with a generic parameter which is constrained to be at least of base class which might get you closer to what you are trying to do. This would look like

More importantly, C# IEqualityComparer Temel Özellikleri ve Kullanımı I have stepped into the trap of thinking that objects, which I use in my code, dirilik be only partially relevant to me, while in case we do OOP every object must be considered in its entirety (things like SOLID help us with that.) C# IEqualityComparer Kullanımı This way, 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 C# IEqualityComparer Kullanımı that LINQ uses when asked to extract distinct objects and perform other equality related operations (see Set operators in this article). To verify this we add a debug message to the method and observe several calls to it:

Klas tanımlama, kodun tekrar kullanılabilirliğini pozitifrır, bakımı kolaylaştırır ve kodun okunabilirliğini geliştirir.

I kişi also make an IEqualityComparer for a "parent class" and use on classes that inherit. I dirilik C# IEqualityComparer nerelerde kullanılıyor have comparer that will behave in a different way, I can make one to compare Value instead of Key.

Protected Internal: Denetleme, türetilen sınıflar yahut aynı derlemedeki sınıflar tarafından erişilebilir hale hasılat. Bu durumda, muayeneün erişimi dardır ve yalnızca türetilen sınıflar veya aynı derlemedeki başka sınıflar aracılığıyla erişilebilir.

The calls to ReferenceEquals and Equals should be prefixed by Object. and base. respectively, so that we know without looking at the rest of the class that those are the methods from Object, derece a helper method in the class

I'm glad the post was of some value to you. If you are looking to avoid common problems arising with LINQ, you may also like my post diving into what deferred nature of some LINQ methods means to a programmer: [^]