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ParallelEnumerable.WithExecutionMode<TSource> Method

Sets the execution mode of the query.

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

public static ParallelQuery<TSource> WithExecutionMode<TSource>(
	this ParallelQuery<TSource> source,
	ParallelExecutionMode executionMode

Type Parameters


The type of elements of source.


Type: System.Linq.ParallelQuery<TSource>
A ParallelQuery on which to set the option.
Type: System.Linq.ParallelExecutionMode
The mode in which to execute the query.

Return Value

Type: System.Linq.ParallelQuery<TSource>
ParallelQuery representing the same query as source, but with the registered execution mode.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type ParallelQuery<TSource>. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).


source is a null reference (Nothing in Visual Basic).


executionMode is not a valid ParallelExecutionMode value.


WithExecutionMode is used multiple times in the query.

The execution mode specifies whether PLINQ will attempt to fall back to sequential execution if it detects certain query shapes. For more information and examples, see How to: Specify the Execution Mode in PLINQ.

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.