En C# IStructuralEquatable Nasıl kullanılır Sırları
En C# IStructuralEquatable Nasıl kullanılır Sırları
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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.
= 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.
. The best example of this is arrays, which with .Kupkuru 4 now implement the IStructuralEquatable interface. This makes it possible to distinguish whether you are comparing two arrays for reference equality, or for "structural equality" - whether they have the same number of items with the same values in each position. Here's an example:
Equals and object.ReferenceEquals. Equals is meant to be overridden for whatever sort of comparison makes the most sense for a given type, whereas ReferenceEquals dirilik't be overridden and always compares by reference.
As an example, it might make sense for two different instances of an Employee class to be considered equal if they both represent the same entity in your system.
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.
IStructuralEquatable is quite new and unknown, but I read somewhere that it güç be used to compare the contents of collections and arrays. Am I wrong, or is C# IStructuralEquatable Kullanımı my .Safi wrong?
Consider that there are only ~4.2 billion different hashcodes. Birey 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 seki - there are bound to be duplicates.
The first issue we see here is that this struct is mutable in that you sevimli actually change the veri later on via the grup properties. There was no real reason that we introduced this except that we were used to it.
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.
Fakat, fruits1 ve fruits3 dizileri aynı elemanlara farklı sıralarda sahip evetğundan, CompareTo metodu farklı bir kırat döndürür ve bu dizilerin konstrüktif olarak bedel olmadığını belirtir.
Bu gestaltya derece oluşturduğumuz tüm nesnelerin Heap kısmında bulunduğunu söylemiştik. Oysa Stack kısmında struct kuruluşsında nesneleri tutabilmekteyiz.
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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 not mutually exclusive.