Difference between ObservableCollection and BindingList

Azhar picture Azhar · Nov 26, 2010 · Viewed 62.9k times · Source

I want to know the difference between ObservableCollection and BindingList because I've used both to notify for any add/delete change in Source, but I actually do not know when to prefer one over the other.

Why would I choose one of the following over the other?

ObservableCollection<Employee> lstEmp = new ObservableCollection<Employee>();

or

BindingList<Employee> lstEmp = new BindingList<Employee>();

Answer

Eilistraee picture Eilistraee · Nov 26, 2010

An ObservableCollection can be updated from UI exactly like any collection. The true difference is rather straightforward:

ObservableCollection<T> implements INotifyCollectionChanged which provides notification when the collection is changed (you guessed ^^) It allows the binding engine to update the UI when the ObservableCollection is updated.

However, BindingList<T> implements IBindingList.

IBindingList provides notification on collection changes, but not only that. It provides a whole bunch of functionality which can be used by the UI to provide a lot more things than only UI updates according to changes, like:

  • Sorting
  • Searching
  • Add through factory (AddNew member function).
  • Readonly list (CanEdit property)

All these functionalities are not available in ObservableCollection<T>

Another difference is that BindingList relays item change notifications when its items implement INotifyPropertyChanged. If an item raises a PropertyChanged event, the BindingList will receive it an raises a ListChangedEvent with ListChangedType.ItemChanged and OldIndex=NewIndex (if an item was replaced, OldIndex=-1). ObservableCollection doesn't relay item notifications.

Note that in Silverlight, BindingList is not available as an option: You can however use ObservableCollections and ICollectionView (and IPagedCollectionView if I remember well).