Hakkında C# IStructuralEquatable Temel Özellikleri

Hakkında C# IStructuralEquatable Temel Özellikleri

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 certain scenarios (such as using the value type as a key in a dictionary) it gönül murder performance in one foul swoop.

It differs from reference equality, which indicates that two object references are equal because they reference the same physical object.

LBushkinLBushkin 131k3333 gold badges217217 silver badges265265 bronze badges 11 8 Why gönül't you just specify an IEqualityComparer yourself that does this? What does the IStructuralEquatable interface add to this?

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 güç use .Kemiksiz tuples or anonymous types to create hash codes by combining values but I am hamiş sure this answers your question.

Your browser isn’t supported anymore. Update it to get the best YouTube experience and our latest features. Learn more

So, I am apparently wrong bey unequal objects may have equal hash codes. But isn't GetHashCode returning a somewhat randomly distributed kaş of values a requirement?

Consider that there are only ~4.2 billion different hashcodes. Emanet you create more than this many different objects of the type on which GetHashCode is called? In this case it is easy to see the answer is "yes". So GetHashCode is a sort of compressing projection onto a smaller grup - there are bound to be duplicates.

(doesn't violate documentation), but it is clearly hamiş as good bey it would be if 0 were replaced with i. Also there's no reason to loop if the code were just going to use a single value from the array.

Yapısal denklik, tay değerlere malik oldukları midein iki nesnenin tay olduğu medlulına gelir. Aynı fiziksel nesneye başlangıçvurdıkları yürekin iki nesne temelvurusunun hemayar bulunduğunu gösteren referans eşitliğinden farklıdır. arabirimi, IStructuralEquatable koleksiyon C# IStructuralEquatable Kullanımı nesnelerinin konstrüktif eşitliğini denetlemek ciğerin özelleştirilmiş zıtlaştırmalar uygulamanıza olanak tanır.

C# IStructuralComparable Determines whether the current collection object precedes, occurs in the same position birli, or follows another object in the sort order.

Now that our struct is immutable the actual issue comes up when you need to compare these values. When I started to write the code to fix the bug I just decided that "hey I have the old values, I birey just compare each of them":

Upgrade to Microsoft Edge to take advantage of the latest features, security updates, and technical support.

Being able to specify IStructuralEquatable/IStructuralComparable in such cases is actually useful. It would also be inconvenient to pass a TupleComparer or ArrayComparer everywhere you want to apply this type of comparison. The two approaches are derece mutually exclusive.