TaskCompletionSource<TResult> TaskCompletionSource<TResult> TaskCompletionSource<TResult> TaskCompletionSource<TResult> Class

定義

デリゲートに関連付けられていない Task<TResult> のプロデューサー側を表し、Task プロパティを通じてコンシューマー側へのアクセスを提供します。 Represents the producer side of a Task<TResult> unbound to a delegate, providing access to the consumer side through the Task property.

generic <typename TResult>
public ref class TaskCompletionSource
public class TaskCompletionSource<TResult>
type TaskCompletionSource<'Result> = class
Public Class TaskCompletionSource(Of TResult)
型パラメーター
TResult

この TaskCompletionSource<TResult> に関連付けられている結果値の型。 The type of the result value assocatied with this TaskCompletionSource<TResult>.

継承
TaskCompletionSource<TResult>TaskCompletionSource<TResult>TaskCompletionSource<TResult>TaskCompletionSource<TResult>

次の例は、使用する方法を示します、 TaskCompletionSource<TResult>:The following example shows how to use a TaskCompletionSource<TResult>:

using System;
using System.Diagnostics;
using System.Threading;
using System.Threading.Tasks;

class TCSDemo
{
    // Demonstrated features:
    // 		TaskCompletionSource ctor()
    // 		TaskCompletionSource.SetResult()
    // 		TaskCompletionSource.SetException()
    //		Task.Result
    // Expected results:
    // 		The attempt to get t1.Result blocks for ~1000ms until tcs1 gets signaled. 15 is printed out.
    // 		The attempt to get t2.Result blocks for ~1000ms until tcs2 gets signaled. An exception is printed out.
    static void Main()
    {
        TaskCompletionSource<int> tcs1 = new TaskCompletionSource<int>();
        Task<int> t1 = tcs1.Task;

        // Start a background task that will complete tcs1.Task
        Task.Factory.StartNew(() =>
        {
            Thread.Sleep(1000);
            tcs1.SetResult(15);
        });

        // The attempt to get the result of t1 blocks the current thread until the completion source gets signaled.
        // It should be a wait of ~1000 ms.
        Stopwatch sw = Stopwatch.StartNew();
        int result = t1.Result;
        sw.Stop();

        Console.WriteLine("(ElapsedTime={0}): t1.Result={1} (expected 15) ", sw.ElapsedMilliseconds, result);

        // ------------------------------------------------------------------

        // Alternatively, an exception can be manually set on a TaskCompletionSource.Task
        TaskCompletionSource<int> tcs2 = new TaskCompletionSource<int>();
        Task<int> t2 = tcs2.Task;

        // Start a background Task that will complete tcs2.Task with an exception
        Task.Factory.StartNew(() =>
        {
            Thread.Sleep(1000);
            tcs2.SetException(new InvalidOperationException("SIMULATED EXCEPTION"));
        });

        // The attempt to get the result of t2 blocks the current thread until the completion source gets signaled with either a result or an exception.
        // In either case it should be a wait of ~1000 ms.
        sw = Stopwatch.StartNew();
        try
        {
            result = t2.Result;

            Console.WriteLine("t2.Result succeeded. THIS WAS NOT EXPECTED.");
        }
        catch (AggregateException e)
        {
            Console.Write("(ElapsedTime={0}): ", sw.ElapsedMilliseconds);
            Console.WriteLine("The following exceptions have been thrown by t2.Result: (THIS WAS EXPECTED)");
            for (int j = 0; j < e.InnerExceptions.Count; j++)
            {
                Console.WriteLine("\n-------------------------------------------------\n{0}", e.InnerExceptions[j].ToString());
            }
        }
    }

}
Imports System.Diagnostics
Imports System.Threading
Imports System.Threading.Tasks

Module TCSDemo
    ' Demonstrated features:
    '   TaskCompletionSource ctor()
    '   TaskCompletionSource.SetResult()
    '   TaskCompletionSource.SetException()
    '   Task.Result
    ' Expected results:
    '   The attempt to get t1.Result blocks for ~1000ms until tcs1 gets signaled. 15 is printed out.
    '   The attempt to get t2.Result blocks for ~1000ms until tcs2 gets signaled. An exception is printed out.

    Private Sub Main()
        Dim tcs1 As New TaskCompletionSource(Of Integer)()
        Dim t1 As Task(Of Integer) = tcs1.Task

        ' Start a background task that will complete tcs1.Task
        Task.Factory.StartNew(Sub()
                                  Thread.Sleep(1000)
                                  tcs1.SetResult(15)
                              End Sub)

        ' The attempt to get the result of t1 blocks the current thread until the completion source gets signaled.
        ' It should be a wait of ~1000 ms.
        Dim sw As Stopwatch = Stopwatch.StartNew()
        Dim result As Integer = t1.Result
        sw.Stop()

        Console.WriteLine("(ElapsedTime={0}): t1.Result={1} (expected 15) ", sw.ElapsedMilliseconds, result)

        ' ------------------------------------------------------------------

        ' Alternatively, an exception can be manually set on a TaskCompletionSource.Task
        Dim tcs2 As New TaskCompletionSource(Of Integer)()
        Dim t2 As Task(Of Integer) = tcs2.Task

        ' Start a background Task that will complete tcs2.Task with an exception
        Task.Factory.StartNew(Sub()
                                  Thread.Sleep(1000)
                                  tcs2.SetException(New InvalidOperationException("SIMULATED EXCEPTION"))
                              End Sub)

        ' The attempt to get the result of t2 blocks the current thread until the completion source gets signaled with either a result or an exception.
        ' In either case it should be a wait of ~1000 ms.
        sw = Stopwatch.StartNew()
        Try
            result = t2.Result

            Console.WriteLine("t2.Result succeeded. THIS WAS NOT EXPECTED.")
        Catch e As AggregateException
            Console.Write("(ElapsedTime={0}): ", sw.ElapsedMilliseconds)
            Console.WriteLine("The following exceptions have been thrown by t2.Result: (THIS WAS EXPECTED)")
            For j As Integer = 0 To e.InnerExceptions.Count - 1
                Console.WriteLine(vbLf & "-------------------------------------------------" & vbLf & "{0}", e.InnerExceptions(j).ToString())
            Next
        End Try
    End Sub

End Module

注釈

多くのシナリオで有効にすると便利です、Task<TResult>を外部の非同期操作を表します。In many scenarios, it is useful to enable a Task<TResult> to represent an external asynchronous operation. TaskCompletionSource<TResult> この目的に提供されます。TaskCompletionSource<TResult> is provided for this purpose. コンシューマーに渡すことができるタスクを作成できます。It enables the creation of a task that can be handed out to consumers. コンシューマー メンバーを使用できます、タスクの同様に、他のメンバー変数をタスクの処理のシナリオの場合と同様です。The consumers can use the members of the task the same way as they would in any other scenario handling task member variables. ただし、ほとんどのタスクとは異なり、TaskCompletionSource によって作成されたタスクの状態がで明示的に制御 TaskCompletionSource メソッド。However, unlike most tasks, the state of a task created by a TaskCompletionSource is controlled explicitly by the methods on TaskCompletionSource. これにより、基になるタスクに反映される外部の非同期操作を完了できます。This enables the completion of the external asynchronous operation to be propagated to the underlying Task. 分離では、コンシューマーができない、対応する TaskCompletionSource にアクセスできない状態に移行することも確認します。The separation also ensures that consumers are not able to transition the state without access to the corresponding TaskCompletionSource. 詳細については、エントリを参照してください。 、TaskCompletionSource 性質<TResult > .NET ブログでの並列プログラミングにします。For more information, see the entry The Nature of TaskCompletionSource<TResult> in the Parallel Programming with .NET blog.

並列拡張機能のサンプルを使用する方法の例を含めることもTaskCompletionSource<TResult>します。The Parallel Extensions samples also contain examples of how to use TaskCompletionSource<TResult>.

コンストラクター

TaskCompletionSource<TResult>() TaskCompletionSource<TResult>() TaskCompletionSource<TResult>() TaskCompletionSource<TResult>()

TaskCompletionSource<TResult> を作成します。 Creates a TaskCompletionSource<TResult>.

TaskCompletionSource<TResult>(Object) TaskCompletionSource<TResult>(Object) TaskCompletionSource<TResult>(Object) TaskCompletionSource<TResult>(Object)

指定された状態を使用して、TaskCompletionSource<TResult> を作成します。 Creates a TaskCompletionSource<TResult> with the specified state.

TaskCompletionSource<TResult>(Object, TaskCreationOptions) TaskCompletionSource<TResult>(Object, TaskCreationOptions) TaskCompletionSource<TResult>(Object, TaskCreationOptions) TaskCompletionSource<TResult>(Object, TaskCreationOptions)

指定された状態とオプションを使用して、TaskCompletionSource<TResult> を作成します。 Creates a TaskCompletionSource<TResult> with the specified state and options.

TaskCompletionSource<TResult>(TaskCreationOptions) TaskCompletionSource<TResult>(TaskCreationOptions) TaskCompletionSource<TResult>(TaskCreationOptions) TaskCompletionSource<TResult>(TaskCreationOptions)

指定されたオプションを使用して、TaskCompletionSource<TResult> を作成します。 Creates a TaskCompletionSource<TResult> with the specified options.

プロパティ

Task Task Task Task

この Task<TResult> によって作成される TaskCompletionSource<TResult> を取得します。 Gets the Task<TResult> created by this TaskCompletionSource<TResult>.

方法

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

指定したオブジェクトが、現在のオブジェクトと等しいかどうかを判断します。 Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

既定のハッシュ関数として機能します。 Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

現在のインスタンスの Type を取得します。 Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

現在の Object の簡易コピーを作成します。 Creates a shallow copy of the current Object.

(Inherited from Object)
SetCanceled() SetCanceled() SetCanceled() SetCanceled()

基になる Task<TResult>Canceled 状態へ遷移させます。 Transitions the underlying Task<TResult> into the Canceled state.

SetException(Exception) SetException(Exception) SetException(Exception) SetException(Exception)

基になる Task<TResult>Faulted 状態に移行させ、それを指定の例外にバインドします。 Transitions the underlying Task<TResult> into the Faulted state and binds it to a specified exception.

SetException(IEnumerable<Exception>) SetException(IEnumerable<Exception>) SetException(IEnumerable<Exception>) SetException(IEnumerable<Exception>)

基になる Task<TResult>Faulted 状態へ移行し、例外オブジェクトのコレクションをそれにバインドします。 Transitions the underlying Task<TResult> into the Faulted state and binds a collection of exception objects to it.

SetResult(TResult) SetResult(TResult) SetResult(TResult) SetResult(TResult)

基になる Task<TResult>RanToCompletion 状態へ遷移させます。 Transitions the underlying Task<TResult> into the RanToCompletion state.

ToString() ToString() ToString() ToString()

現在のオブジェクトを表す文字列を返します。 Returns a string that represents the current object.

(Inherited from Object)
TrySetCanceled() TrySetCanceled() TrySetCanceled() TrySetCanceled()

基になる Task<TResult>Canceled 状態への遷移を試みます。 Attempts to transition the underlying Task<TResult> into the Canceled state.

TrySetCanceled(CancellationToken) TrySetCanceled(CancellationToken) TrySetCanceled(CancellationToken) TrySetCanceled(CancellationToken)

基になる Task<TResult>Canceled 状態への遷移を試みるとともに、キャンセル トークンをキャンセルされたタスクに格納できるようにします。 Attempts to transition the underlying Task<TResult> into the Canceled state and enables a cancellation token to be stored in the canceled task.

TrySetException(Exception) TrySetException(Exception) TrySetException(Exception) TrySetException(Exception)

基になる Task<TResult>Faulted 状態への移行を試み、それを指定の例外にバインドします。 Attempts to transition the underlying Task<TResult> into the Faulted state and binds it to a specified exception.

TrySetException(IEnumerable<Exception>) TrySetException(IEnumerable<Exception>) TrySetException(IEnumerable<Exception>) TrySetException(IEnumerable<Exception>)

基になる Task<TResult>Faulted 状態への移行を試み、例外オブジェクトのコレクションをそれにバインドします。 Attempts to transition the underlying Task<TResult> into the Faulted state and binds a collection of exception objects to it.

TrySetResult(TResult) TrySetResult(TResult) TrySetResult(TResult) TrySetResult(TResult)

基になる Task<TResult>RanToCompletion 状態への遷移を試みます。 Attempts to transition the underlying Task<TResult> into the RanToCompletion state.

適用対象

スレッド セーフ

すべてのメンバーTaskCompletionSource<TResult>はスレッド セーフであると同時に複数のスレッドから使用できます。 All members of TaskCompletionSource<TResult> are thread-safe and may be used from multiple threads concurrently.

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