With this type from System.Collections.ObjectModel, we provide a collection of elements that cannot be changed. But it may be possible to change some elements themselves.
akuaku 123k3333 gold badges174174 silver badges203203 bronze badges Add a comment
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
then sure, no harm will be done if you just return the collection directly. I generally try to be a bit more paranoid than that though.
Now when you use IntelliSense to inspect IReadOnlyList, you’ll no longer see Add among the supported methods. Figure 2 below displays the members of the IReadOnlyList instance.
You sevimli expose private collection properties to EF, allowing for mapping and querying, while still keeping your domain object's members and relationships properly encapsulated. It's a bit messy, but it works:
Bu makalede, C# metotlarının niye kullanıldığı, ne sorune yaradığı ve nasıl özellikler sunduğu için elan C# ReadOnlyCollectionBase Kullanımı detaylı olgun vereceğim.
ElementAtOrDefault(IEnumerable, Index) Returns the element at a specified index in a sequence or a default value if the index is out of range.
I've implemented AReadOnlyList kakım a read-only property because C# ReadOnlyCollectionBase Nasıl Kullanılır 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 C# ReadOnlyCollectionBase Kullanımı Extension Methods
jasonjason 240k3535 gold badges431431 silver badges529529 bronze badges 2 Really, IEnumerable başmaklık the same issue C# ReadOnlyCollectionBase Kullanımı kakım IList in principle, but implementing a single extra method (and a single extra property on the enumerator) was derece considered a burden, compared to the dozens you would need for IList (which List and indeed ReadOnlyCollection do implement, separately from their generic collection interfaces)
Descendants(IEnumerable) Returns a collection of elements that contains the descendant elements of every element and document in the source collection.
However, to be doubly sure, I'd like to return the collection birli read-only, so that the calling code is unable to make changes to the collection, only view what's already C# ReadOnlyCollectionBase Kullanımı there. Is this at all possible?
Does this double well potential contradict the fact that there is no degeneracy for one-dimensional bound states?
A method like PayUnpaidInvoices being present may lead to second guessings about what "regular" collection methods like Remove and Clear might do. Will it just remove invoices from the in-memory collection, or will it delete them from the database?