Hakkında herşey C# IStructuralEquatable Temel Özellikleri

Hakkında herşey C# IStructuralEquatable Temel Özellikleri

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The "No" in part 2 of the answer is actually incorrect. Note: Tried editing the answer, but apparently some think that the highest rated answer being incorrect is hamiş reason enough to approve a correction edit.

In certain scenarios (such bey using the value type birli a key in a dictionary) it yaşama murder performance in one foul swoop.

That is right! When we override Equals we must also override and implement GetHashCode. I am no HashCode expert, but in the same article from Sergey is a snippet of using a ValueTuple to simplify this entire call to 1 line of code just like our fancy ValueTuple Equality above.

IStructuralComparable arayüzü, umumiyetle Array ve Tuple üzere muta bünyeları tarafından uygulanır. Bu bilgi mimariları, elemanlarının sıralamasını ve yapısını dikkate alarak karşıtlaştırma yapar.

I'm amazed that the most important reason is not mentioned here. IEquatable was introduced mainly for structs for two reasons:

Structural equality means that two objects are equal because they have equal 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 C# IStructuralEquatable Kullanımı comparisons to check for the structural equality of collection objects.

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

When an implementer overrides the virtual Equals method in a struct, the purpose is to provide a more efficient means of performing the value equality check and optionally to base the comparison on some subset of the struct's field or properties.

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In addition to this awesome blog Frank and I also dicussed all of this awesome in detail on Merge Conflict on episode 111:

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

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 gönül just compare each of them":

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

However, this is hamiş so great if you are using the struct in a dictionary kakım my good friend Dustin mentioned to me because a Dictionary will always use the object version of Equals, which falls back to boxing :(