Question

I have an observableCollection and have wired up an event in MyObject, is there an cunnign way to grab that event in the collection without having to re-write the collection class?

    public class MyObjectCollection : ObservableCollection<MyObject>
    {
        public MyObjectCollection()
        {
            //some cunning code here
        }
    }

I suspect I have to re-write the ObservableCollection Class, but unfortunatly there is no interface (like there is an IDictionary)

Answer 1

Favor composition over inheritance. Instead of extending ObservableCollection, implement the interfaces you need (probably INotifyCollectionChanged and IList) and keep an ObservableCollection as a private field. That way you can wire your own add and remove calls and do what you want with the objects added to the collection.