c# - Why is .NET ObservableCollection<T> implemented as a class and not an interface? -

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in reading observer design pattern, noticed implemented using interfaces. in java, java.util.observable implementation class. shouldn't c# , java versions use interfaces ?

scott

well, implements inotifycollectionchanged , inotifypropertychanged. however, interestingly, doesn't implement new iobservable<t> interface .net 4.0, might have expected.

it arguably useful there generic form of inotifycollectionchanged... don't know of one.


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