C# IStructuralEquatable Kullanımı - Genel Bakış

C# IStructuralEquatable Kullanımı - Genel Bakış

Blog Article

Why do we have IStructuralComparable and IStructuralEquatable when there already exist the IComparable and IEquatable interfaces? The answer I would offer is that, in general, it's desirable to differentiate between reference comparisons and structural comparisons.

In this case you don't want to change your class implementation so you don't wantoverride the Equals method. this will define a general way to compare objects in your application.

Reference types (read classes) don't benefit bey much. The IEquatable implementation does let you avoid a cast from System.Object but that's a very trivial gain. I still like IEquatable to be implemented for my classes since it logically makes the intent explicit.

Kakım far birli I see this is only exposed through the StructuralComparisons class. The only way I dirilik figure out to make this useful is to make a StructuralEqualityComparer helper class birli follow:

This code technically works, but is sort of a hot mess and is not really maintainable. Anyone using the library would have to write this code bey well. The next logical step would be to just use .Equals on the entire metrics.

Structural equality means that two objects are equal because they have equal C# IStructuralEquatable Kullanımı values. It differs from reference equality, which indicates that two object references are equal because they reference the same physical object. The IStructuralEquatable interface enables you to implement customized comparisons to check for the structural equality of collection objects.

IStructuralEquatable is quite new and unknown, but I read somewhere that it emanet be used to compare the contents of collections and arrays. Am I wrong, or is my .Kupkuru wrong?

şu demek oluyor ki anlayacağınız “int” kabil, “bool” kabil boy bos tipli bir oynak peyda etmek istiyorsanız struct yapısını tercih edebilirsiniz.

Reading through the excellent blog post by Sergey on struct equality performance he mentions that the default implementations are pretty slow and using boxing for each member. Additionally, he mentions that a memory comparison may hamiş give you the correct results in this super simple example:

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.

This member is an explicit interface member implementation. It güç be used only when the Array instance is cast to an IStructuralEquatable interface.

The example on MSDN gives part of the answer here; it seems to be useful for heterogeneous equality, rather than homogeneous equality - i.e. for testing whether two objects (/values) of potentially different types

Here the comparison is different for value type arrays and custom arrays. In .Kupkuru 4.0 int, string will internally implement IEquatable for custom types we have to externally implement the IEquatable.

While writing my own immutable ByteArray class that uses a byte array internally, I implemented the IStructuralEquatable interface.