ObservableCollection Doesn't support AddRange method, so I get notified for each item added, besides what about INotifyCollectionChanging?

Question

I want to be able to add a range and get updated for the entire bulk.

I also want to be able to cancel the action before it\'s done (i.e. collection changing besides

Answer 1

The C# summarized descendant.

More reading: http://blogs.msdn.com/b/nathannesbit/archive/2009/04/20/addrange-and-observablecollection.aspx

public sealed class ObservableCollectionEx : ObservableCollection
{
    #region Ctor

    public ObservableCollectionEx()
    {
    }

    public ObservableCollectionEx(List list) : base(list)
    {
    }

    public ObservableCollectionEx(IEnumerable collection) : base(collection)
    {
    }

    #endregion

    /// 
 
    /// Adds the elements of the specified collection to the end of the ObservableCollection(Of T). 
    /// 
 
    public void AddRange(
        IEnumerable itemsToAdd,
        ECollectionChangeNotificationMode notificationMode = ECollectionChangeNotificationMode.Add)
    {
        if (itemsToAdd == null)
        {
            throw new ArgumentNullException("itemsToAdd");
        }
        CheckReentrancy();

        if (notificationMode == ECollectionChangeNotificationMode.Reset)
        {
            foreach (var i in itemsToAdd)
            {
                Items.Add(i);
            }

            OnPropertyChanged(new PropertyChangedEventArgs("Count"));
            OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
            OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));

            return;
        }

        int startIndex = Count;
        var changedItems = itemsToAdd is List ? (List) itemsToAdd : new List(itemsToAdd);
        foreach (var i in changedItems)
        {
            Items.Add(i);
        }

        OnPropertyChanged(new PropertyChangedEventArgs("Count"));
        OnPropertyChanged(new PropertyChangedEventArgs("Item[]"));
        OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, changedItems, startIndex));
    }

    public enum ECollectionChangeNotificationMode
    {
        /// 

        /// Notifies that only a portion of data was changed and supplies the changed items (not supported by some elements,
        /// like CollectionView class).
        /// 
        Add,

        /// 

        /// Notifies that the entire collection was changed, does not supply the changed items (may be inneficient with large
        /// collections as requires the full update even if a small portion of items was added).
        /// 
        Reset
    }
}