Büyülenme Hakkında C# IStructuralEquatable nedir

Büyülenme Hakkında C# IStructuralEquatable nedir

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If equality is derece needed for the derived class you can skip IEquatable but you need to override the CanEqual to prevent it being equal with base classes (unless of course they should be considered equal).

= to provide value equality checks (vs the default reference equality check). The MSDN documentation suggests you only do it for immutable types. There are also issues involving interfaces and operator overloading.

Other types which implement structural equality/comparability include tuples and anonymous types - which both clearly benefit from the ability to perform comparison based on their structure and content. A question you didn't ask is:

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. Birli the output from the example shows, the first three method calls return true, whereas the fourth call returns false.

You generic method saf a type parameter T but the type is derece part of the signature of the function so how is T supposed to be used in the function? Anyway, you hayat use .Kupkuru tuples or anonymous types to create hash codes by combining values but I am hamiş sure this answers your question.

Your concern is that Object.GetHashCode() does derece provide values that are stable and the concern is very valid bey dirilik be seen in the first box headed by Caution in C# IStructuralEquatable Kullanımı the documentation:

After some more testing I found that any two arrays with the same first element have the same hash. I still think this is strange behavior.

The following example creates two identical 3-tuple objects whose components consist of three Double values. The value of the second component is Double.NaN. The example then calls the Tuple.Equals method, and it calls the IStructuralEquatable.Equals method three times. The first time, it passes the default equality comparer that is returned by the EqualityComparer.

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 not give you the correct results in this super simple example:

Yapısal eşitlik, eşit bileğerlere sahip oldukları karınin iki nesnenin müsavi olduğu demeına hasılat. Aynı fiziki nesneye başlangıçvurdıkları bağırsakin dü nesne sarrafiyevurusunun bedel bulunduğunu gösteren başvuru eşitliğinden farklıdır. arabirimi, IStructuralEquatable derme nesnelerinin konstrüktif eşitliğini denetlemek karınin özelleştirilmiş katlaştırmalar uygulamanıza olanak tanılamar.

C# IStructuralEquatable Defines methods to support the comparison of objects for structural equality.

That is, you sevimli create your own definition of structural equality and specify that this definition be used with a collection type that accepts the IStructuralEquatable interface. The interface başmaklık two members: Equals, which tests for equality by using a specified IEqualityComparer implementation, and GetHashCode, which returns identical hash codes for objects that are equal.

The IStructuralEquatable interface supports only custom comparisons for structural equality. The IStructuralComparable interface supports custom structural comparisons for sorting and ordering.

Specifically, I do derece know the exact type of the object. The only assumption I make is that it inherit from IStructuralEquatable.