En C# IEnumerable Nedir Sırları
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IEnumerable tüm verileri hileıp memory de sara, sorgulama kârlemlerini memory üzerinden yaparken IQueryable ise şartlara bağlı query oluşturarak vasıtasız veritabanı üzerinden sorgulama medarımaişetlemi yapar.
So when you have to simply iterate through the in-memory collection, use IEnumerable, if you need to do any manipulation with the collection like Dataset and other data sources, use IQueryable
As per other answers, the evaluation of the result was deferred until calling ToList or similar invocation methods for example ToArray.
Karma fonksiyonlarının özelleştirilmesi ve done dokumalarında başarımı bırakmak dâhilin GetHashCode yöntemi kullanılır.
The expression sevimli simply be a constant expression of the object itself or a more complex tree of a composed set of query operators and operands. The query provider's IQueryProvider.Execute() or IQueryProvider.CreateQuery() methods are called with an Expression
Quoting that article, 'Bey per the MSDN documentation, calls made on IQueryable operate by building up the internal expression tree instead.
Ryan LundyRyan Lundy 208k4141 gold badges183183 silver badges214214 bronze badges 3 4 Then why do we need this IEnumerable abstraction, if the only thing it does is just provide an access to Enumerator? Why don't just use Enumerator instead
ServyServy 203k2727 gold badges342342 silver badges458458 bronze badges 1 @Jay thanks, just noticed that when re-reading.
Now what makes IEnumerable really stand out is iterator blocks (the yield keyword in C#). Iterator blocks implement the IEnumerable interface like a List or an Array, but they're very special because unlike C# IEnumerable Temel Özellikleri a List or Array, they often only hold the state for a single item at a time. So if you want to loop over C# IEnumerable Nasıl Kullanılır the lines in a very large file, for example, you gönül write an iterator block to handle the file input.
Marc GravellMarc Gravell 1.0m271271 gold badges2.6k2.6k silver badges2.9k2.9k bronze badges 1 1 The mistake with "Reset" was with just having one type of enumerable. IMHO, there should have been an IMultipassEnumerable, inheriting IEnumerable, which would support Reset and C# IEnumerable Nerelerde Kullanılıyor guarantee that multiple passes will either return identical data or throw an exception; an ordinary IEnumerable whose collection was modified should be allowed to return 'sensible' data if it's able to do so or throw an exception if it birey't, and an ISafeEnumerable, which would be expected to work sensibly (without throwing an exception) even if a collection changes. A bit late now to change things, though.
" This is false, because the where clause is getting called on an IEnumerable and that only knows how to loop through objects which are C# IEnumerable Kullanımı already coming from the database. If you made the return of AllSpotted() and the parameters of Feline() and Canine() into IQueryable, then the filter would happen in SQL and this answer would make sense.
Bir sonraki elementin varlığını sınayan MoveNext ve muteber elementi veren GetCurrent metodlarına sahiptir.
Bu interface, C# IEnumerable Nedir uygulandığı sınıfa GetEnumerator adlı bir metot kazandırır ve bu metot geriye IEnumerator interface’ini implement eden bir derslik döndürür.
IEnumerable tipi veriyi önce belleğe atıp arkası sıra bellekteki bu done üzerinden belirtilen koşulları çtuzakıştırır ve veriye uygular.