The individual calls to IEqualityComparer.Equals end and the IStructuralEquatable.Equals method returns a value either when a method call returns false or after all array elements or tuple components have been compared.
Now, when we call Equals ourselves it will directly call our new fancy Equals that takes in a ScreenMetrics, which is great.
This is really amazing code and works great for .Safi Standard libraries. If you are in a .Kupkuru Core 2.1 application there is an even cooler way of doing this:
Default property. The second time, it passes the default equality comparer that is returned by the StructuralComparisons.StructuralEqualityComparer property. The third time, it passes the custom NanComparer object. Bey the output from the example shows, the first three method calls return true, whereas the fourth call returns false.
Although I think the gains from not boxing will be less than the cost for having CanEqual. In that case you should seal your types and you no longer need CanEqual. Sealing also saf some performance benefits.
The IStructuralEquatable interface enables you to implement customized comparisons to check for the structural equality of collection objects.
The IEquatable implementation will require one less cast for these classes and kakım a result will be slightly faster than the standard object.Equals method that would be used otherwise. Kakım an example see the different implementation of the two methods:
I've noticed these two interfaces, and several associated classes, have been added in .Kemiksiz 4. They seem a bit superfluous to me; I've read several blogs about them, but I still güç't figure out what mesele they solve that was tricky before .NET 4.
comparer IEqualityComparer İki nesnenin müsavi olup olmadığını gitmek için kullanılacak yöntemi teşhismlayan nesne.
In all my years of development and blogging I never thought I would be writing about how amazing a C# struct is, how awesome IEquatable is, and how C# 7 features make implementing all of it mind blowing.
Each of your objects should use a hashcode based on the contents of the object. If you have a value type containing 3 ints, use those when computing the hash code. Like this, all objects with identical content will have the same hash code, independent of app domain and other circumstances.
The contract of Equals differs from that of IStructuralEquatable, in that it indicates whether 2 objects are logically equal.
Here the comparison is different for value type arrays and custom arrays. In C# IStructuralEquatable Nasıl kullanılır .Safi 4.0 int, string will internally implement IEquatable for custom types we have to externally implement the IEquatable.
However, this is not so great if you are using the struct in a dictionary bey my good friend Dustin mentioned to me because a Dictionary will always use the object version of Equals, which falls back to boxing :(