Observable.DistinctUntilChanged<TSource> Method (IObservable<TSource>, IEqualityComparer<TSource>)

Returns an observable sequence that contains only distinct contiguous elements according to the comparer.

Namespace:  System.Reactive.Linq
Assembly:  System.Reactive (in System.Reactive.dll)

public static IObservable<TSource> DistinctUntilChanged<TSource>(
	this IObservable<TSource> source,
	IEqualityComparer<TSource> comparer

Type Parameters


The type of source.


Type: System.IObservable<TSource>
An observable sequence to retain distinct contiguous elements for.
Type: System.Collections.Generic.IEqualityComparer<TSource>
The equality comparer for computed key values.

Return Value

Type: System.IObservable<TSource>
An observable sequence only containing the distinct contiguous elements from the source sequence.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IObservable<TSource>. When you use instance method syntax to call this method, omit the first parameter. For more information, see https://msdn.microsoft.com/en-us/library/bb384936(v=vs.103) or https://msdn.microsoft.com/en-us/library/bb383977(v=vs.103).