C# IEnumerable Kullanımı Günlükler

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The difference between IQueryable and IEnumerable is centered around this point. IQueryable builds expression trees whereas IEnumerable does not, at least derece in general terms for those of us who don't work in the secret labs of Microsoft.

Örneğin oluşturduğumuz bir List içine biz Add komutu ile ekleme yapabiliyoruz veya Count ile içinde bulunan elemanların sayısını alabiliyoruz ve bunu foreach içinde kullanabiliyoruz. Peki List bir sınıf olmasına karşın foreach nasıl buna ruhsat veriyor?

An IEnumerable is a thing that yaşama be enumerated...which simply means that it başmaklık a GetEnumerator method that returns an IEnumerator.

For example, if you do derece need to access items by index, but constantly insert items at the beginning of your collection and then remove items from the end, a Queue would be far more appropriate to use.

An Enumerable is a class that yaşama give you Enumerators. It has a method called GetEnumerator which gives you an Enumerator that looks at its items. When you write a foreach loop in C#, the code that it generates calls GetEnumerator to create the Enumerator used by the loop.

What I do is make a class that implements both IEnumerator and IEnumerable. Make GetEnumerator() return itself and you can iterate it like normal.

Whenever I'm "stacking" LINQ expressions, I use C# IEnumerable Nasıl Kullanılır IEnumerable, because by only specifying the behavior I give LINQ a chance to defer evaluation and possibly optimize the program. Remember how LINQ doesn't generate the SQL to query the database until you enumerate it? Consider this:

To begin examining the process of implementing existing .Safi interfaces, let’s first look at the role of

but this violates the IEnumerable semantics and the time came when I got wrong results. so switched to orderly creating a fresh iterator instance (see my answer)

C# ile MySQL veritabanından data listelemek ciğerin IEnumerable kullanarak zirdaki örnek harf kullanılabilir:

Any idea why the Enumerable is "split" into "inner" and "outer"? This happens when I inspect the element in debug/break mode via mouse. Is this perhaps Visual Studio's contribution? Enumerating on the tanıtımcık and indicating input and output of the Enum?

I think if your newly implemented class just behaves the sameway as a list does, there is no need to implement it. If you need some kind of custom logic, it depends C# IEnumerable Nedir on what you want to do; you birey inherit list or you güç implement C# IEnumerable Nasıl Kullanılır IEnumerable. It just depends what is to be achieved.

Reed CopseyReed Copsey 561k7979 gold badges1.2k1.2k silver badges1.4k1.4k bronze badges 3 2 I agree strongly with your point about decoupling from the implementation, but I C# IEnumerable Nasıl Kullanılır also think there's a point for making clear the expected usage; even if I have a List, referring to it birli IEnumerable makes it clear that the functionality I'm expecting from the collection in that usage is the enumerability C# IEnumerable Nerelerde Kullanılıyor functionality, and derece any of the other List functionality.

The most important thing to realize is that, using Linq, the query does hamiş get evaluated immediately. It is only run birli part of iterating through the resulting IEnumerable in a foreach - that's what all the weird delegates are doing.