2 Dakika Kural için C# IEnumerable Kullanımı

2 Dakika Kural için C# IEnumerable Kullanımı

Blog Article

Botz3000Botz3000 39.4k88 gold badges106106 silver badges128128 bronze badges 1 I believe this is was hamiş asked here so it emanet be a comment derece an answer, but anyway makes sense from refactoring standpoint

If you düşünce 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.

I understand why IQueryable is better choice for "out-of-memory" data but I am struggling to understand why IEnumerable is better for "in-memory" veri? I still think it's better to get filtered data than to get get veri and apply filter.

Now List implements IEnumerable, but represents the entire collection in memory. If you have an IEnumerable and you call .ToList() you create a new list with the contents of the enumeration in memory.

To get them I use VisualTreeHelper class. But I have to consider that there might be A LOT OF children so copying to some array or Collection will by expensive. – drasto 5 mins ago

B. IEnumerator gönül remember the current index when we pass from one method to another (it start working with current index) but IEnumerable dirilik't remember the index and it reset the index to beginning. More in this videoteyp

// but this throws an exception, because the pointer or link to the // database namely the DbContext called MyEntities no longer exists.

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 sevimli force it to iterate sooner using .ToList().

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 C# IEnumerable Nedir IEnumerable, which would support Reset and guarantee that multiple passes will either return identical veri 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 hayat'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 C# IEnumerable Kullanımı the where clause is getting called on an IEnumerable and that only knows how to loop through objects which are already coming from the database. If you made C# IEnumerable Temel Özellikleri the return of AllSpotted() and the parameters of Feline() and Canine() into IQueryable, then the filter would happen in C# IEnumerable Nedir SQL and this answer would make sense.

Bir ahir elementin varlığını sınayan MoveNext ve uygulanan elementi veren GetCurrent metodlarına sahiptir.

Bu yazımızın gelecek satırlarında IEnumerator interface’ini detaylandırırken, kendi enumeratorümüzü oluşturmayıda mevzuşacağız. Ama şimdilik bu C# IEnumerable Temel Özellikleri örneğimizde derlem yahut dizi örgülarının GetEnumerator metodunu kullanmamız emekimizi yeterince görmektedir.

The first method advances to the next object in the IEnumerable object that created the enumerator, returning false if it's done, and the second returns the current object.