C# ReadOnlyCollectionBase Kullanımı Için 5-İkinci Trick

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 data in a List, then you dirilik use the List GetEnumerator method to retrieve an Enumerator object, which you dirilik then return to the izlence using your class. Listing 1 saf the basics of this class (I've called it PhvReadOnlyList).

A note. Read-only status is not transferred to other references. You cannot replace the references with other StringBuilder references or the null literal.

I avoid using ReadOnlyCollection kakım much bey possible, it is actually considerably slower than just using a alışılagelen List.

Equals metodunda, Point3D dershaneının X, Y ve Z bileğerlerinin vesair nokta ile aynı olup olmadığı denetleme edilir. GetHashCode metodunda ise nesnenin hash kodu oluşturularak yapısal eşitlik muhaliflaştırmalarında kullanılır.

Can you arrange 25 whole numbers (derece necessarily all different) so that the sum of any three successive terms is even but the sum of C# ReadOnlyCollectionBase Nerelerde Kullanılıyor all 25 is odd?

Suppose you need to return a list of all authors from the database kakım shown in the code snippet given below.

On the other hand, if you're exposing a read-only view of a mutable collection, then this advice is still valid, although I would probably expose it bey IReadOnlyCollection (which didn't exist when I wrote this).

protected virtual ICollection EmployeesInternal get; private takım; = new List(); // this will expose collection contents to public, seemingly unneccessary `Skip` statement will prevent casting back to Collection

Does this double well potential contradict the fact that there is no degeneracy for one-dimensional bound states?

Movie about a planet where seeds must be harvested just right in order to liberate a valuable crystal within

However, the syntax is awkward. Adding an extension method can simplify that syntax tremendously. Extension methods have at least three convenient features: The first is C# ReadOnlyCollectionBase Temel Özellikleri that they attach themselves to whatever classes you specify, automatically appearing in the IntelliSense dropdown lists for those objects; second, they're automatically passed whatever object they're called from bey their first parameter; third, when an extension method is used with a generic class (for instance, List), the method automatically figures out the data type of the generic parameter.

However, a read-only collection doesn't provide Add and Remove methods for C# ReadOnlyCollectionBase Nerelerde Kullanılıyor 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).

The IEnumerable interface is yet another interface used often to represent read-only C# ReadOnlyCollectionBase Nerelerde Kullanılıyor collections of data. If you simply want to enumerate the elements of a collection, you sevimli use IEnumerable kakım shown below.

(There are plenty of other options for C# ReadOnlyCollectionBase Kullanımı wrapping trivially - the nice thing about Skip over Select/Where is that there's no delegate to execute pointlessly for each iteration.)