C# ReadOnlyCollectionBase Nerelerde Kullanılıyor Herkes İçin Eğlenceli Olabilir

C# ReadOnlyCollectionBase Nerelerde Kullanılıyor Herkes İçin Eğlenceli Olabilir

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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 yaşama use the List GetEnumerator method to retrieve an Enumerator object, which you can then return to the program using your class. Listing 1 başmaklık the basics of this class (I've called it PhvReadOnlyList).

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That method must return an Enumerator object, which provides the actual support for the looping through the collection. Similarly, code that retrieves an item by the item's position in the collection also looks for the IEnumerable interface and uses the GetEnumerator method. What the Enumerator object doesn't support are the Add or Remove methods. Ignoring the ReadOnlyCollectionBase

Objects everywhere), and it makes the construction wordier (hayat't use .ToList or collection initializers). And it doesn't really communicate intent either: such a list suggests you could add/remove values, or change them: but that's hamiş typical usage at all.

A collection that is read-only is simply a collection with C# ReadOnlyCollectionBase Kullanımı a wrapper that prevents modifying the collection; therefore, if changes are made to the underlying collection, the read-only collection reflects those changes.

Is there any reason to expose an internal collection bey a ReadOnlyCollection rather than an IEnumerable if the calling code only iterates over the collection?

Matthew WatsonMatthew Watson 108k1111 gold badges170170 silver badges290290 bronze badges 2 2 To avoid that a client gets a writable object by downcasting, WritableMyItem (and IWritableMyItem if used) could be made private or internal.

Fakat, articles1 C# ReadOnlyCollectionBase Temel Özellikleri ve articles3 dizileri aynı makale başlangıçlıklarına farklı sıralarda ehil başüstüneğundan, CompareTo metodu farklı bir fehamet döndürür ve bu dizilerin strüktürel olarak bedel olmadığını belirtir.

Exposing the array directly to those using C# ReadOnlyCollectionBase Kullanımı it means that they kişi modify it - this is a violation of encapsulation and veri hiding.

A ReadOnlyCollectionBase instance is always read-only. See CollectionBase for a modifiable version of this C# ReadOnlyCollectionBase Nasıl Kullanılır class.

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

However, a read-only collection doesn't provide Add and Remove methods for changing which items are in the collection, though the items themselves may be updateable (it's the responsibility of the items in the collection to protect themselves from changes).

End Sub And that's all you need to write. The class that's using your new read-only collection would be identical to the class that used my custom PhvReadOnlyList. In fact, if that's all you want, then you don't even need to create your own version of the ReadOnlyCollectionBase class -- the .

I don't know if there is any way of protecting non-atomic elements without cloning them before placing them in the read only list. Share Improve this answer Follow