ActionBlock<TInput> Constructors

Definition

Namespace:

System.Threading.Tasks.Dataflow

Assembly:

System.Threading.Tasks.Dataflow.dll

Overloads

ActionBlock<TInput>(Action<TInput>)	Initializes a new instance of the ActionBlock<TInput> class with the specified action.
ActionBlock<TInput>(Func<TInput,Task>)	Initializes a new instance of the ActionBlock<TInput> class with the specified action.
ActionBlock<TInput>(Action<TInput>, ExecutionDataflowBlockOptions)	Initializes a new instance of the ActionBlock<TInput> class with the specified action and configuration options.
ActionBlock<TInput>(Func<TInput,Task>, ExecutionDataflowBlockOptions)	Initializes a new instance of the ActionBlock<TInput> class with the specified action and configuration options.

ActionBlock<TInput>(Action<TInput>)

Source:

ActionBlock.cs

Initializes a new instance of the ActionBlock<TInput> class with the specified action.

public:
 ActionBlock(Action<TInput> ^ action);

public ActionBlock (Action<TInput> action);

new System.Threading.Tasks.Dataflow.ActionBlock<'Input> : Action<'Input> -> System.Threading.Tasks.Dataflow.ActionBlock<'Input>

Public Sub New (action As Action(Of TInput))

Parameters

action

Action<TInput>

The action to invoke with each data element received.

Exceptions

ArgumentNullException

action is null.

ActionBlock<TInput>(Func<TInput,Task>)

Source:

ActionBlock.cs

Initializes a new instance of the ActionBlock<TInput> class with the specified action.

public:
 ActionBlock(Func<TInput, System::Threading::Tasks::Task ^> ^ action);

public ActionBlock (Func<TInput,System.Threading.Tasks.Task> action);

new System.Threading.Tasks.Dataflow.ActionBlock<'Input> : Func<'Input, System.Threading.Tasks.Task> -> System.Threading.Tasks.Dataflow.ActionBlock<'Input>

Public Sub New (action As Func(Of TInput, Task))

Parameters

action

Func<TInput,Task>

The action to invoke with each data element received.

Exceptions

ArgumentNullException

action is null.

ActionBlock<TInput>(Action<TInput>, ExecutionDataflowBlockOptions)

Source:

ActionBlock.cs

Initializes a new instance of the ActionBlock<TInput> class with the specified action and configuration options.

public:
 ActionBlock(Action<TInput> ^ action, System::Threading::Tasks::Dataflow::ExecutionDataflowBlockOptions ^ dataflowBlockOptions);

public ActionBlock (Action<TInput> action, System.Threading.Tasks.Dataflow.ExecutionDataflowBlockOptions dataflowBlockOptions);

new System.Threading.Tasks.Dataflow.ActionBlock<'Input> : Action<'Input> * System.Threading.Tasks.Dataflow.ExecutionDataflowBlockOptions -> System.Threading.Tasks.Dataflow.ActionBlock<'Input>

Public Sub New (action As Action(Of TInput), dataflowBlockOptions As ExecutionDataflowBlockOptions)

Parameters

action

Action<TInput>

The action to invoke with each data element received.

dataflowBlockOptions

ExecutionDataflowBlockOptions

The options with which to configure this ActionBlock<TInput>.

Exceptions

ArgumentNullException

action is null.

-or-

dataflowBlockOptions is null.

Examples

The following example shows how to use the ActionBlock<TInput>(Action<TInput>, ExecutionDataflowBlockOptions) constructor to create a new ActionBlock<TInput> object. This code example is part of a larger example provided for the How to: Specify the Degree of Parallelism in a Dataflow Block topic.

// Performs several computations by using dataflow and returns the elapsed
// time required to perform the computations.
static TimeSpan TimeDataflowComputations(int maxDegreeOfParallelism,
   int messageCount)
{
   // Create an ActionBlock<int> that performs some work.
   var workerBlock = new ActionBlock<int>(
      // Simulate work by suspending the current thread.
      millisecondsTimeout => Thread.Sleep(millisecondsTimeout),
      // Specify a maximum degree of parallelism.
      new ExecutionDataflowBlockOptions
      {
         MaxDegreeOfParallelism = maxDegreeOfParallelism
      });

   // Compute the time that it takes for several messages to
   // flow through the dataflow block.

   Stopwatch stopwatch = new Stopwatch();
   stopwatch.Start();

   for (int i = 0; i < messageCount; i++)
   {
      workerBlock.Post(1000);
   }
   workerBlock.Complete();

   // Wait for all messages to propagate through the network.
   workerBlock.Completion.Wait();

   // Stop the timer and return the elapsed number of milliseconds.
   stopwatch.Stop();
   return stopwatch.Elapsed;
}

' Demonstrates how to specify the maximum degree of parallelism 
' when using dataflow.
Friend Class Program
   ' Performs several computations by using dataflow and returns the elapsed
   ' time required to perform the computations.
   Private Shared Function TimeDataflowComputations(ByVal maxDegreeOfParallelism As Integer, ByVal messageCount As Integer) As TimeSpan
      ' Create an ActionBlock<int> that performs some work.
      Dim workerBlock = New ActionBlock(Of Integer)(Function(millisecondsTimeout) Pause(millisecondsTimeout), New ExecutionDataflowBlockOptions() With { .MaxDegreeOfParallelism = maxDegreeOfParallelism})
         ' Simulate work by suspending the current thread.
         ' Specify a maximum degree of parallelism.

      ' Compute the time that it takes for several messages to 
      ' flow through the dataflow block.

      Dim stopwatch As New Stopwatch()
      stopwatch.Start()

      For i As Integer = 0 To messageCount - 1
         workerBlock.Post(1000)
      Next i
      workerBlock.Complete()

      ' Wait for all messages to propagate through the network.
      workerBlock.Completion.Wait()

      ' Stop the timer and return the elapsed number of milliseconds.
      stopwatch.Stop()
      Return stopwatch.Elapsed
   End Function

   Private Shared Function Pause(ByVal obj As Object)
      Thread.Sleep(obj)
      Return Nothing
   End Function

ActionBlock<TInput>(Func<TInput,Task>, ExecutionDataflowBlockOptions)

Source:

ActionBlock.cs

Initializes a new instance of the ActionBlock<TInput> class with the specified action and configuration options.

public:
 ActionBlock(Func<TInput, System::Threading::Tasks::Task ^> ^ action, System::Threading::Tasks::Dataflow::ExecutionDataflowBlockOptions ^ dataflowBlockOptions);

public ActionBlock (Func<TInput,System.Threading.Tasks.Task> action, System.Threading.Tasks.Dataflow.ExecutionDataflowBlockOptions dataflowBlockOptions);

new System.Threading.Tasks.Dataflow.ActionBlock<'Input> : Func<'Input, System.Threading.Tasks.Task> * System.Threading.Tasks.Dataflow.ExecutionDataflowBlockOptions -> System.Threading.Tasks.Dataflow.ActionBlock<'Input>

Public Sub New (action As Func(Of TInput, Task), dataflowBlockOptions As ExecutionDataflowBlockOptions)

Parameters

action

Func<TInput,Task>

The action to invoke with each data element received.

dataflowBlockOptions

ExecutionDataflowBlockOptions

The options with which to configure this ActionBlock<TInput>.

Exceptions

ArgumentNullException

action is null.

-or-

dataflowBlockOptions is null.