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ParallelEnumerable.Except<TSource> Method (ParallelQuery<TSource>, ParallelQuery<TSource>, IEqualityComparer<TSource>)

.NET Framework (current version)

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Produces the set difference of two parallel sequences by using the specified IEqualityComparer<T> to compare values.

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

public static ParallelQuery<TSource> Except<TSource>(
	this ParallelQuery<TSource> first,
	ParallelQuery<TSource> second,
	IEqualityComparer<TSource> comparer


Type: System.Linq.ParallelQuery<TSource>

A sequence whose elements that are not also in second will be returned.

Type: System.Linq.ParallelQuery<TSource>

A sequence whose elements that also occur in the first sequence will cause those elements to be removed from the returned sequence.

Type: System.Collections.Generic.IEqualityComparer<TSource>

IEqualityComparer<T> to compare values.

Return Value

Type: System.Linq.ParallelQuery<TSource>

A sequence that contains the set difference of the elements of two sequences.

Type Parameters


The type of the elements of the input sequences.

Exception Condition

first or second is a null reference (Nothing in Visual Basic).


The query was canceled with the token passed in through WithCancellation.


One or more exceptions occurred during the evaluation of the query.

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Windows Phone
Available since 8.1
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