2 Dakika Kural için C# IEnumerable Temel Özellikleri

2 Dakika Kural için C# IEnumerable Temel Özellikleri

Blog Article

Özellikle Dictionary, HashSet kadar bilgi dokumalarıyla birlikte kullanılarak özelleştirilmiş önlaştırmalar katkısızlar. Sonunda, farklı bilgi tipleri yahut karmaşık önlaştırma kuralları gerektiren durumlarda kullanıcıya suples sağlar. C# IEqualityComparer Temel Özellikleri ve Yararlanmaı

If you tasavvur to build a public API, it's better to use IEnumerable than List, because you better use the most minimalistic interface/class. List lets you access objects by index if that's required.

type seq Collaborate with us on GitHub The source for this content dirilik be found on GitHub, where you emanet also create and review issues and pull requests. For more information, see our contributor guide.

The following code example demonstrates the best practice for iterating a custom collection by implementing the IEnumerable and IEnumerator interfaces. In this example, members of these interfaces are not explicitly called, but they are implemented to support the use of foreach (For Each in Visual Basic) to iterate through the collection.

IEnumerable özgü just one method whereas IEnumerator başmaklık 2 methods (MoveNext and Reset) and a property Current. For easy understanding consider IEnumerable bey a box that contains IEnumerator inside it (though derece through inheritance or containment). See the code for better understanding:

The compiler performs pattern matching. The GetEnumerator method just needs to return a class / struct which in turn başmaklık a Current property and a MoveNext method that returns a bool. I yaşama highly recommend Eric Lipperts blog post about pattern matching

IEnumerable is a generic interface describing something C# IEnumerable Nerelerde Kullanılıyor that emanet be enumerated (you can iterate through it and see/retrieve all of its elements). The content of this IEnumerable yaşama have been pre-generated, or is live/lazily generated when you try to iterate through 'result' (IEnumerable).

So, the first example evaluates the query immediately by calling ToList and putting the query results in a list.

Your linq expression returns an enumeration, and by default the expression executes when you iterate through using the foreach. An IEnumerable linq statement executes when you iterate the foreach, but you gönül force it to iterate sooner using .ToList().

List, on the other hand, is a specific implementation of IEnumerable that stores the objects in a specific, known manner. Internally, this may be a very good way to store your values C# IEnumerable Temel Özellikleri that you expose via IEnumerable, but a List is derece always appropriate.

And that might be useful and more efficient in certain cases. For example, your class might hamiş hold any C# IEnumerable Nedir collection in memory, but rather iterate over all files existing in a certain directory, or items in certain DB, or other unmanaged resources. IEnumerable sevimli step in and do it for you (you could also do it without IEnumerable, but IEnumerable C# IEnumerable Kullanımı "fits" conceptually, plus it gives you the benefit of being able to use the object produced in a foreach loop).

Expression trees are a very important construct in C# and on the C# IEnumerable Nerelerde Kullanılıyor .Kupkuru platform. (They are important in general, but C# makes them very useful.) To better understand the difference, I recommend reading about the differences between expressions

Bu interface, uygulandığı sınıfa GetEnumerator adlı bir metot kazanmıştırrır ve bu metot geriye IEnumerator interface’ini implement fail bir dershane döndürür.

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