ForEach(TSource) Method (Partitioner(TSource), ParallelOptions, Action(TSource))

Task Parallel System.Threading

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Executes a for each operation on a Partitioner in which iterations may run in parallel.

Namespace: System.Threading.Tasks
Assembly: System.Threading (in System.Threading.dll)

Syntax

Visual Basic (Declaration)
Public Shared Function ForEach(Of TSource) ( _ source As Partitioner(Of TSource), _ parallelOptions As ParallelOptions, _ body As Action(Of TSource) _ ) As ParallelLoopResult

C#
public static ParallelLoopResult ForEach<TSource>( Partitioner<TSource> source, ParallelOptions parallelOptions, Action<TSource> body )

Parameters

source: Type: System.Collections.Concurrent..::.Partitioner<(Of <(TSource>)>)
The Partitioner that contains the original data source.

parallelOptions: Type: System.Threading.Tasks..::.ParallelOptions
A ParallelOptions instance that configures the behavior of this operation.

body: Type: System..::.Action<(Of <(TSource>)>)
The delegate that is invoked once per iteration.

Type Parameters

TSource: The type of the elements in source.

Return Value

A ParallelLoopResult structure that contains information on what portion of the loop completed.

Remarks

The Partitioner is used to retrieve the elements to be processed, in place of the original data source. If the current element's index is desired, the source must be an OrderablePartitioner.

The body delegate is invoked once for each element in the source Partitioner. It is provided with the current element as a parameter.

Exceptions

Exception	Condition
System..::.ArgumentNullException	The exception that is thrown when the source argument is null.
System..::.ArgumentNullException	The exception that is thrown when the parallelOptions argument is null.
System..::.ArgumentNullException	The exception that is thrown when the body argument is null.
System..::.OperationCanceledException	The exception that is thrown when the CancellationToken in the parallelOptions argument is set
System..::.InvalidOperationException	The exception that is thrown when the SupportsDynamicPartitions property in the source Partitioner returns false.
System..::.InvalidOperationException	The exception that is thrown when any methods in the source Partitioner return null.
System..::.InvalidOperationException	The exception that is thrown when the GetPartitions() method in the source Partitioner does not return the correct number of partitions.
System..::.InvalidOperationException	The exception that is thrown when the GetPartitions() method in the source Partitioner returns an IList with at least one null value.
System..::.InvalidOperationException	The exception that is thrown when the GetDynamicPartitions() method in the source Partitioner returns an IEnumerable whose GetEnumerator() method returns null.
System..::.AggregateException	The exception that is thrown to contain an exception thrown from one of the specified delegates.
System..::.ObjectDisposedException	The exception that is thrown when the the CancellationTokenSource associated with the the CancellationToken in the parallelOptions has been disposed.