Parallel Class

Definition

Namespace:: System.Threading.Tasks

Assemblies:: mscorlib.dll, System.Threading.Tasks.Parallel.dll

Assemblies:: netstandard.dll, System.Threading.Tasks.Parallel.dll

Assembly:: System.Threading.Tasks.Parallel.dll

Assembly:: mscorlib.dll

Assembly:: netstandard.dll

Source:: Parallel.cs

Source:: Parallel.cs

Source:: Parallel.cs

Source:: Parallel.cs

Source:: Parallel.cs

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Provides support for parallel loops and regions.

public ref class Parallel abstract sealed

public static class Parallel

type Parallel = class

Public Class Parallel

Inheritance: Object
Parallel

Examples

This example demonstrates several approaches to implementing a parallel loop using multiple language constructs.

using System.Threading.Tasks; 
class Test
{
 static int N = 1000;

 static void TestMethod()
 {
 // Using a named method.
 Parallel.For(0, N, Method2);

 // Using an anonymous method.
 Parallel.For(0, N, delegate(int i)
 {
 // Do Work.
 });

 // Using a lambda expression.
 Parallel.For(0, N, i =>
 {
 // Do Work.
 });
 }

 static void Method2(int i)
 {
 // Do work.
 }
}

Imports System.Threading.Tasks

Module Module1

 Sub Main()
 Dim N As Integer = 1000

 ' Using a named method
 Parallel.For(0, N, AddressOf Method2)

 ' Using a lambda expression.
 Parallel.For(0, N, Sub(i)
 ' Do Work
 End Sub)
 End Sub

 Sub Method2(ByVal i As Integer)
 ' Do work.
 End Sub

End Module

Remarks

The Parallel class provides library-based data parallel replacements for common operations such as for loops, for each loops, and execution of a set of statements.

Methods

Name	Description
For(Int32, Int32, Action<Int32,ParallelLoopState>)	Executes a `for` loop in which iterations may run in parallel and the state of the loop can be monitored and manipulated.
For(Int32, Int32, Action<Int32>)	Executes a `for` loop in which iterations may run in parallel.
For(Int32, Int32, ParallelOptions, Action<Int32,ParallelLoopState>)	Executes a `for` loop in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
For(Int32, Int32, ParallelOptions, Action<Int32>)	Executes a `for` loop in which iterations may run in parallel and loop options can be configured.
For(Int64, Int64, Action<Int64,ParallelLoopState>)	Executes a `for` loop with 64-bit indexes in which iterations may run in parallel and the state of the loop can be monitored and manipulated.
For(Int64, Int64, Action<Int64>)	Executes a `for` loop with 64-bit indexes in which iterations may run in parallel.
For(Int64, Int64, ParallelOptions, Action<Int64,ParallelLoopState>)	Executes a `for` loop with 64-bit indexes in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
For(Int64, Int64, ParallelOptions, Action<Int64>)	Executes a `for` loop with 64-bit indexes in which iterations may run in parallel and loop options can be configured.
For<TLocal>(Int32, Int32, Func<TLocal>, Func<Int32,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `for` loop with thread-local data in which iterations may run in parallel, and the state of the loop can be monitored and manipulated.
For<TLocal>(Int32, Int32, ParallelOptions, Func<TLocal>, Func<Int32,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `for` loop with thread-local data in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
For<TLocal>(Int64, Int64, Func<TLocal>, Func<Int64,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `for` loop with 64-bit indexes and thread-local data in which iterations may run in parallel, and the state of the loop can be monitored and manipulated.
For<TLocal>(Int64, Int64, ParallelOptions, Func<TLocal>, Func<Int64,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `for` loop with 64-bit indexes and thread-local data in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForAsync<T>(T, T, CancellationToken, Func<T,CancellationToken,ValueTask>)	Executes a for loop in which iterations may run in parallel.
ForAsync<T>(T, T, Func<T,CancellationToken,ValueTask>)	Executes a for loop in which iterations may run in parallel.
ForAsync<T>(T, T, ParallelOptions, Func<T,CancellationToken,ValueTask>)	Executes a for loop in which iterations may run in parallel.
ForEach<TSource,TLocal>(IEnumerable<TSource>, Func<TLocal>, Func<TSource,ParallelLoopState,Int64,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with thread-local data on an IEnumerable in which iterations may run in parallel and the state of the loop can be monitored and manipulated.
ForEach<TSource,TLocal>(IEnumerable<TSource>, Func<TLocal>, Func<TSource,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with thread-local data on an IEnumerable in which iterations may run in parallel, and the state of the loop can be monitored and manipulated.
ForEach<TSource,TLocal>(IEnumerable<TSource>, ParallelOptions, Func<TLocal>, Func<TSource,ParallelLoopState,Int64,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with thread-local data and 64-bit indexes on an IEnumerable in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource,TLocal>(IEnumerable<TSource>, ParallelOptions, Func<TLocal>, Func<TSource,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with thread-local data on an IEnumerable in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource,TLocal>(OrderablePartitioner<TSource>, Func<TLocal>, Func<TSource,ParallelLoopState,Int64,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with thread-local data on a OrderablePartitioner<TSource> in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource,TLocal>(OrderablePartitioner<TSource>, ParallelOptions, Func<TLocal>, Func<TSource,ParallelLoopState,Int64,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with 64-bit indexes and with thread-local data on a OrderablePartitioner<TSource> in which iterations may run in parallel , loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource,TLocal>(Partitioner<TSource>, Func<TLocal>, Func<TSource,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with thread-local data on a Partitioner in which iterations may run in parallel and the state of the loop can be monitored and manipulated.
ForEach<TSource,TLocal>(Partitioner<TSource>, ParallelOptions, Func<TLocal>, Func<TSource,ParallelLoopState,TLocal,TLocal>, Action<TLocal>)	Executes a `foreach` (`For Each` in Visual Basic) operation with thread-local data on a Partitioner in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(IEnumerable<TSource>, Action<TSource,ParallelLoopState,Int64>)	Executes a `foreach` (`For Each` in Visual Basic) operation with 64-bit indexes on an IEnumerable in which iterations may run in parallel, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(IEnumerable<TSource>, Action<TSource,ParallelLoopState>)	Executes a `foreach` (`For Each` in Visual Basic) operation on an IEnumerable in which iterations may run in parallel, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(IEnumerable<TSource>, Action<TSource>)	Executes a `foreach` (`For Each` in Visual Basic) operation on an IEnumerable in which iterations may run in parallel.
ForEach<TSource>(IEnumerable<TSource>, ParallelOptions, Action<TSource,ParallelLoopState,Int64>)	Executes a `foreach` (`For Each` in Visual Basic) operation with 64-bit indexes on an IEnumerable in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(IEnumerable<TSource>, ParallelOptions, Action<TSource,ParallelLoopState>)	Executes a `foreach` (`For Each` in Visual Basic) operation on an IEnumerable in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(IEnumerable<TSource>, ParallelOptions, Action<TSource>)	Executes a `foreach` (`For Each` in Visual Basic) operation on an IEnumerable in which iterations may run in parallel and loop options can be configured.
ForEach<TSource>(OrderablePartitioner<TSource>, Action<TSource,ParallelLoopState,Int64>)	Executes a `foreach` (`For Each` in Visual Basic) operation on a OrderablePartitioner<TSource> in which iterations may run in parallel and the state of the loop can be monitored and manipulated.
ForEach<TSource>(OrderablePartitioner<TSource>, ParallelOptions, Action<TSource,ParallelLoopState,Int64>)	Executes a `foreach` (`For Each` in Visual Basic) operation on a OrderablePartitioner<TSource> in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(Partitioner<TSource>, Action<TSource,ParallelLoopState>)	Executes a `foreach` (`For Each` in Visual Basic) operation on a Partitioner in which iterations may run in parallel, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(Partitioner<TSource>, Action<TSource>)	Executes a `foreach` (`For Each` in Visual Basic) operation on a Partitioner in which iterations may run in parallel.
ForEach<TSource>(Partitioner<TSource>, ParallelOptions, Action<TSource,ParallelLoopState>)	Executes a `foreach` (`For Each` in Visual Basic) operation on a Partitioner in which iterations may run in parallel, loop options can be configured, and the state of the loop can be monitored and manipulated.
ForEach<TSource>(Partitioner<TSource>, ParallelOptions, Action<TSource>)	Executes a `foreach` (`For Each` in Visual Basic) operation on a Partitioner in which iterations may run in parallel and loop options can be configured.
ForEachAsync<TSource>(IAsyncEnumerable<TSource>, CancellationToken, Func<TSource,CancellationToken,ValueTask>)	Executes a `for-each` operation on an IEnumerable<T> in which iterations may run in parallel.
ForEachAsync<TSource>(IAsyncEnumerable<TSource>, Func<TSource,CancellationToken,ValueTask>)	Executes a `for-each` operation on an IEnumerable<T> in which iterations may run in parallel.
ForEachAsync<TSource>(IAsyncEnumerable<TSource>, ParallelOptions, Func<TSource,CancellationToken,ValueTask>)	Executes a `for-each` operation on an IEnumerable<T> in which iterations may run in parallel.
ForEachAsync<TSource>(IEnumerable<TSource>, CancellationToken, Func<TSource,CancellationToken,ValueTask>)	Executes a `for-each` operation on an IEnumerable<T> in which iterations may run in parallel.
ForEachAsync<TSource>(IEnumerable<TSource>, Func<TSource,CancellationToken,ValueTask>)	Executes a `for-each` operation on an IEnumerable<T> in which iterations may run in parallel.
ForEachAsync<TSource>(IEnumerable<TSource>, ParallelOptions, Func<TSource,CancellationToken,ValueTask>)	Executes a `for-each` operation on an IEnumerable<T> in which iterations may run in parallel.
Invoke(Action[])	Executes each of the provided actions, possibly in parallel.
Invoke(ParallelOptions, Action[])	Executes each of the provided actions, possibly in parallel, unless the operation is cancelled by the user.

Applies to

Thread Safety

All public and protected members of Parallel are thread-safe and may be used concurrently from multiple threads.

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URL: https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.parallel?view=net-10.0

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