C# ReadOnlyCollectionBase Kullanımı Için 5-İkinci Trick

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I'm going to start by being perverse and pretending that the ReadOnlyCollectionBase class doesn't exist. If that were true and you wanted to create a read-only collection, you'd create a class that only returned an Enumerator object. A class that just implements IEnumerable is, according to my definitions, a read-only collection class. Generating that GetEnumerator object from your class isn't difficult if you keep your class data in a class that itself implements IEnumerable -- a List, for instance. If you do keep your veri in a List, then you kişi use the List GetEnumerator method to retrieve an Enumerator object, which you can then return to the yetişek using your class. Listing 1 saf the basics of this class (I've called it PhvReadOnlyList).

-SortedDictionary: Bu derlem HashTable ve SortedList sınıflarının yoğurulmasıyla oluşmuş bir sınıftır. Aralarında çok narin farklar vardır. SortedList’ten henüz aşkın bellek kullanır.

Sevimli you arrange 25 whole numbers (not necessarily all different) so that the sum of any three successive terms is even but the sum of all 25 is odd?

If your veri birey be enumerated, you dirilik use Enumerable.ToList method to cast your collection to List and call AsReadOnly on it.

Imagine we have existing paradigma with Organization => Employees already set up. To apply this technique, we need to change Organization paradigma a bit:

Also, native collections hayat't be enhanced with extra veri. You'll recognize this next time you find that you pass in (Collection, Extra) to more than one or two methods. It indicates that "Extra" belongs with the object containing your collection.

Çaldatmaışma zamanında yalnızca constructor içerisinde bedel ataması konstrüksiyonlabilmektedir. Damarı bozuk halde salt okunur bir alana kıymetiharbiye atanamaz ikazsı vermektedir. Readonly değişici tanımı süflidaki gibidir.

It depends on how much you trust the calling code. If you're in complete control over everything that will ever call this member and you guarantee

I've implemented AReadOnlyList kakım a read-only property because I'm assuming that if you don't want programs adding or removing items from your collection, you probably don't want programs shoving whole new collections into your property, either. Simplifying Code with Extension Methods

If you do this then there's nothing stopping your callers casting the IEnumerable back to ICollection and then modifying it. ReadOnlyCollection removes this possibility, although it's still possible to access the C# ReadOnlyCollectionBase Kullanımı underlying writable collection via reflection.

ICollection is such abstraction and you could say that ICollection does derece have an exact corresponding peer in C# ReadOnlyCollectionBase Kullanımı the generic world; IEnumerable is the closest.

SingleOrDefault(IEnumerable, Func) Returns the only element of a sequence that satisfies C# ReadOnlyCollectionBase Nerelerde Kullanılıyor a specified condition or a default value if no such element exists; this method throws an exception if more than one element satisfies the C# ReadOnlyCollectionBase Nasıl Kullanılır condition.

ObservableCollection gönül bind to ListViewCollection in such a way that changes to ListViewCollection do hamiş get pushed back into ObservableCollection. The original C# ReadOnlyCollectionBase Kullanımı ReadOnlyObservableCollection, however, throws an exception if you try to modify the collection.

If however your intent is to prevent the calling code from observing updates from other threads you'll have to fall back to solutions already mentioned, to perform a deep or shallow copy depending on your need.