Burada enum kümesinde olmayan bir elemana erişmek isteriz. Runtime da hiç bir problem gayrimümkün ve bize dijital değeri yahut olması gereken dijital değeri döner , hata olduğunun farkına varmayız. Tekrar de denetçi etmekte kâr var :)
Pek çok programlama dili ile teknolojisine geniş perspektiften yaklaşarak, yeni kellelayanlardan profesyonellere derece her seviyeden bireye isabetli içeriklerle donatılmıştır.
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?
When writing programs in C# with the help of LINQ I have come across the IEqualityComparer generic interface several times. The name conveys the purpose of the interface clearly, still, surprisingly, my first attempts to apply it were marked by strong confusion - the thing merely didn't work the way I wanted it to. Moreover, after going to Google and StackOverflow I have noticed that I'm not the only one to face difficulties with it.
This was a point of some debate and there are arguments on three sides: choose the more specific of the types, choose the more general of the types, or have type inference yapan. I will derece rehash the whole C# IEqualityComparer nerelerde kullanılıyor argument but suffice to say that the "choose the more general" side won the day.
We first need to define a class that needs comparison with another instance of the class. For this post, we’ll be using a Player class with two properties.
The issue here is that comparing floating-point numbers for equality might not work kakım expected, due to minute rounding errors. There are different methods of comparing floating-point numbers for near-equality
There are multiple ways to tackle C# IEqualityComparer nerelerde kullanılıyor this and tell LINQ how the objects should be compared to each other. I will cover the use of IEqualityComparer. The interface contains two methods:
EDIT2: As mentioned in C# IEqualityComparer nerelerde kullanılıyor the comments doing reflection within Equals or even GetHashCode is a bad idea kakım it´s usually quite slow and kişi often be avoided. If you know the properties to be checked for eqality at compile-time you should definitly C# IEqualityComparer Kullanımı include them within those two methods as doing C# IEqualityComparer Kullanımı so gives you much more safety.
Daha zait selen karınin Microsoft Learn’daki “C# 12'bile Neler Yeni” sayfasına ve Roslyn Özellik Durumu sayfasına delik atabilirsiniz. Siz bile bu yenilikçi özellikleri deneyerek nominalm geliştirme deneyiminizi geliştirebilirsiniz.
Örnekte, kullanıcıların müsavi olup olmadığını denetçi ederken kullanıcı adları dikkate münfailtır.
You could do this more elegantly using FluentAssertions library. It has plenty assertion methods for collections.
No property will be added at runtime. I only want to ensure that nobody modify this class without make some test red. We are hundreds in the team and some guy could modify the class without notice side effects.
If things don't seem to be working (such kakım duplicate key errors when doing ToDictionary) put a breakpoint inside Equals to make sure it's being hit and make sure you have GetHashCode defined (with override keyword).