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

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走了就别回头了
走了就别回头了 2020-11-22 16:19

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

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  • 陌清茗
    陌清茗 (楼主)
    2020-11-22 16:42

    ObservableRangeCollection should pass a test like

    [Test]
public void TestAddRangeWhileBoundToListCollectionView()
{
    int collectionChangedEventsCounter = 0;
    int propertyChangedEventsCounter = 0;
    var collection = new ObservableRangeCollection();

    collection.CollectionChanged += (sender, e) => { collectionChangedEventsCounter++; };
    (collection as INotifyPropertyChanged).PropertyChanged += (sender, e) => { propertyChangedEventsCounter++; };

    var list = new ListCollectionView(collection);

    collection.AddRange(new[] { new object(), new object(), new object(), new object() });

    Assert.AreEqual(4, collection.Count);
    Assert.AreEqual(1, collectionChangedEventsCounter);
    Assert.AreEqual(2, propertyChangedEventsCounter);
}



    otherwise we get 
    


    System.NotSupportedException : Range actions are not supported.

    


    while using with a control.
    


    I do not see an ideal solution, but NotifyCollectionChangedAction.Reset instead of Add/Remove partially solve the problem. See http://blogs.msdn.com/b/nathannesbit/archive/2009/04/20/addrange-and-observablecollection.aspx as was mentioned by net_prog
    
    
    
             
    
                                                        
    
            
            
    
              
                
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