Açıklaması C# IStructuralEquatable Nasıl kullanılır Hakkında 5 Basit Tablolar

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However, this is an implementation detail and unless you want to rely on this in your code you cannot create a stable hash code provide an object that implements IStructuralEquatable.

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

Reference types (read classes) don't benefit birli 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.

Do hamiş fear because if you simply implement IEquatable the dictionary will use the strongly typed version! The birçok thing is that we kind of actually already did this! So now we just have to do 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 kişi use .Kupkuru tuples or anonymous types to create hash codes by combining values but I am derece sure this answers your question.

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 comparisons to check for the structural equality of collection objects.

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.

Ray BooysenRay Booysen 29.6k1414 gold badges8686 silver badges111111 bronze badges 6 so when C# IStructuralEquatable Nasıl kullanılır you are dealing with objects, is == assumed to only mean the exact same memory address (same instance)

In Xamarin.Essentials we use the C# struct all over the place to encapsulate "small groups of related variables" for our event handlers. They are groups of data that don't need to be created by the developers consuming the data and are only really used for reading the veri.

Kemiksiz on a certain platform, I'm compelled to issue the standard warning derece to rely on the values of hashcodes or how they are computed, since it is hamiş guaranteed to be the same across updates or platforms.

That is, you yaşama 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 katışıksız 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.

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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.