/// <summary>Observe CollectionChanged:Replace and take single item.</summary>
public static IObservable <OldNewPair <T> > ObserveReplaceChanged <T>(this INotifyCollectionChanged source)
{
var result = source.CollectionChangedAsObservable()
.Where(e => e.Action == NotifyCollectionChangedAction.Replace)
.Select(e => new OldNewPair <T>((T)e.OldItems[0], (T)e.NewItems[0]));
return(result);
}
/// <summary>Observe CollectionChanged:Move.</summary>
public static IObservable <OldNewPair <T[]> > ObserveMoveChangedItems <T>(this INotifyCollectionChanged source)
{
var result = source.CollectionChangedAsObservable()
.Where(e => e.Action == NotifyCollectionChangedAction.Move)
.Select(e => new OldNewPair <T[]>(e.OldItems.Cast <T>().ToArray(), e.NewItems.Cast <T>().ToArray()));
return(result);
}
/// <summary>Observe CollectionChanged:Remove.</summary>
public static IObservable <T[]> ObserveRemoveChangedItems <T>(this INotifyCollectionChanged source)
{
var result = source.CollectionChangedAsObservable()
.Where(e => e.Action == NotifyCollectionChangedAction.Remove)
.Select(e => e.OldItems.Cast <T>().ToArray());
return(result);
}
/// <summary>Observe CollectionChanged:Remove and take single item.</summary>
public static IObservable <T> ObserveRemoveChanged <T>(this INotifyCollectionChanged source)
{
var result = source.CollectionChangedAsObservable()
.Where(e => e.Action == NotifyCollectionChangedAction.Remove)
.Select(e => (T)e.OldItems[0]);
return(result);
}
/// <summary>Observe CollectionChanged:Reset.</summary>
public static IObservable <Unit> ObserveResetChanged <T>(this INotifyCollectionChanged source)
{
var result = source.CollectionChangedAsObservable()
.Where(e => e.Action == NotifyCollectionChangedAction.Reset)
.Select(_ => new Unit());
return(result);
}
/// <summary> /// Observe CollectionChanged:Replace. /// </summary> public static IObservable <OldNewPair <T[]> > ObserveReplaceChangedItems <T>(this INotifyCollectionChanged source) => source.CollectionChangedAsObservable() .Where(e => e.Action == NotifyCollectionChangedAction.Replace) .Select(e => new OldNewPair <T[]>(e.OldItems.Cast <T>().ToArray(), e.NewItems.Cast <T>().ToArray()));
/// <summary> /// Observe CollectionChanged:Move and take single item. /// </summary> public static IObservable <OldNewPair <T> > ObserveMoveChanged <T>(this INotifyCollectionChanged source) => source.CollectionChangedAsObservable() .Where(e => e.Action == NotifyCollectionChangedAction.Move) .Select(e => new OldNewPair <T>((T)e.OldItems[0], (T)e.NewItems[0]));
/// <summary> /// Observe CollectionChanged:Add. /// </summary> public static IObservable <T[]> ObserveAddChangedItems <T>(this INotifyCollectionChanged source) => source.CollectionChangedAsObservable() .Where(e => e.Action == NotifyCollectionChangedAction.Add) .Select(e => e.NewItems.Cast <T>().ToArray());
/// <summary> /// Observe CollectionChanged:Add and take single item. /// </summary> public static IObservable <T> ObserveAddChanged <T>(this INotifyCollectionChanged source) => source.CollectionChangedAsObservable() .Where(e => e.Action == NotifyCollectionChangedAction.Add) .Select(e => (T)e.NewItems[0]);
