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:
Note that IEqualityComparer may (and should) be used to perform more complex comparisons, however its implementation won't get much more complex in most cases.
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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Bir dahaki sefere versiyon yaptığımda kullanılmak üzere girişimı, elektronik posta adresimi ve web site adresimi bu tarayıcıya kaydet.
Therefore, when testing two instances of T for equality, because T saf no internal understanding of equality, you will have to make an explicit choice of a IEqualityComparer instance which performs the test according to your specific requirements.
Hem teorik bilgilerini çoğaltmak hem bile uygulamalı deneyim isabet etmek kucakin bu platformu bileğerlendirebilirsin.
After inspecting multiple SO questions and answers related to the topic birli well as some other articles I have both found the solution that fitted my needs for the moment and got some understanding of the way IEqualityComparer is actually used by LINQ operators. Here I will try to explain what I got from there.
Coming soon: Throughout 2024 we will be phasing out C# IEqualityComparer Kullanımı GitHub Issues kakım the feedback mechanism for content and replacing it with a new feedback system. For more information see: .
operating on different types of classes, even complex types including sub-objects or nested lists. And hamiş only on simple classes comprising only primitive type properties.
SnowbearSnowbear 3,66311 gold badge1919 silver badges2323 bronze badges $endgroup$ 2 $begingroup$ If I'm not mistaken, C# IEqualityComparer Nasıl Kullanılır the GetHashCode() function normally takes the object's memory address into it's calculation. I'll have to do some more reading up on that. $endgroup$
So there you go. In this situation, type inference chooses the more general type and infers C# IEqualityComparer Kullanımı that C# IEqualityComparer Temel Özellikleri ve Kullanımı the call means Distinct. Type inference never takes the return type
And yes, after this the output of the izlence doesn't change at all. So, what the hell is LINQ doing and why doesn't it even try to use the equality comparer that we have provided? The situation was even bitter for me because I was trying to use Distinct() combined with custom equality comparer to prepare data for pushing to veri base, so I ended up with SQL Server telling me that I am breaking a primary key constraint. Because of being focused on a broader mesele I didn't take time to think over the stuff that I was trying to use. What I missed was the fact that LINQ, being a query engine, tries to perform as efficiently birli possible.
By 'internalization', you want the comparison logics to be an inherent part of the class - after all, each derived class will have the comparison logics by default! So chances are that you want to tweak your C# IEqualityComparer nerelerde kullanılıyor biçim a bit? yes? no?