Task.WhenAll Task.WhenAll Task.WhenAll Task.WhenAll Method

定義

指定されたすべてのタスクが完了してから完了するタスクを作成します。Creates a task that will complete when all of the supplied tasks have completed.

オーバーロード

WhenAll(IEnumerable<Task>) WhenAll(IEnumerable<Task>) WhenAll(IEnumerable<Task>) WhenAll(IEnumerable<Task>)

列挙可能なコレクション内のすべての Task オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task objects in an enumerable collection have completed.

WhenAll(Task[]) WhenAll(Task[]) WhenAll(Task[]) WhenAll(Task[])

配列内のすべての Task オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task objects in an array have completed.

WhenAll<TResult>(IEnumerable<Task<TResult>>) WhenAll<TResult>(IEnumerable<Task<TResult>>) WhenAll<TResult>(IEnumerable<Task<TResult>>) WhenAll<TResult>(IEnumerable<Task<TResult>>)

列挙可能なコレクション内のすべての Task<TResult> オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task<TResult> objects in an enumerable collection have completed.

WhenAll<TResult>(Task<TResult>[]) WhenAll<TResult>(Task<TResult>[]) WhenAll<TResult>(Task<TResult>[]) WhenAll<TResult>(Task<TResult>[])

配列内のすべての Task<TResult> オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task<TResult> objects in an array have completed.

WhenAll(IEnumerable<Task>) WhenAll(IEnumerable<Task>) WhenAll(IEnumerable<Task>) WhenAll(IEnumerable<Task>)

列挙可能なコレクション内のすべての Task オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task objects in an enumerable collection have completed.

public:
 static System::Threading::Tasks::Task ^ WhenAll(System::Collections::Generic::IEnumerable<System::Threading::Tasks::Task ^> ^ tasks);
public static System.Threading.Tasks.Task WhenAll (System.Collections.Generic.IEnumerable<System.Threading.Tasks.Task> tasks);
static member WhenAll : seq<System.Threading.Tasks.Task> -> System.Threading.Tasks.Task
Public Shared Function WhenAll (tasks As IEnumerable(Of Task)) As Task

パラメーター

tasks
IEnumerable<Task>

完了を待機するタスク。The tasks to wait on for completion.

戻り値

指定されたすべてのタスクの完了を表すタスク。A task that represents the completion of all of the supplied tasks.

例外

tasks 引数が null でした。The tasks argument was null.

tasks コレクションに null タスクが含まれていました。The tasks collection contained a null task.

次の例では、配列内の Url に ping を実行するタスクのセットを作成します。The following example creates a set of tasks that ping the URLs in an array. タスクが格納されている、List<Task>に渡されるコレクション、WhenAll(IEnumerable<Task>)メソッド。The tasks are stored in a List<Task> collection that is passed to the WhenAll(IEnumerable<Task>) method. 呼び出し後、Waitメソッドにより、すべてのスレッドが完了した例では、検査、Task.Statusプロパティをすべてのタスクに障害が発生しているかどうかを判断します。After the call to the Wait method ensures that all threads have completed, the example examines the Task.Status property to determine whether any tasks have faulted.

using System;
using System.Collections.Generic;
using System.Net.NetworkInformation;
using System.Threading;
using System.Threading.Tasks;

public class Example
{
   public static void Main()
   {
      int failed = 0;
      var tasks = new List<Task>();
      String[] urls = { "www.adatum.com", "www.cohovineyard.com",
                        "www.cohowinery.com", "www.northwindtraders.com",
                        "www.contoso.com" };
      
      foreach (var value in urls) {
         var url = value;
         tasks.Add(Task.Run( () => { var png = new Ping();
                                     try {
                                        var reply = png.Send(url);
                                        if (! (reply.Status == IPStatus.Success)) {
                                           Interlocked.Increment(ref failed);
                                           throw new TimeoutException("Unable to reach " + url + ".");
                                        }
                                     }
                                     catch (PingException) {
                                        Interlocked.Increment(ref failed);
                                        throw;
                                     }
                                   }));
      }
      Task t = Task.WhenAll(tasks);
      try {
         t.Wait();
      }
      catch {}   

      if (t.Status == TaskStatus.RanToCompletion)
         Console.WriteLine("All ping attempts succeeded.");
      else if (t.Status == TaskStatus.Faulted)
         Console.WriteLine("{0} ping attempts failed", failed);      
   }
}
// The example displays output like the following:
//       5 ping attempts failed
Imports System.Collections.Generic
Imports System.Net.NetworkInformation
Imports System.Threading
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim failed As Integer = 0
      Dim tasks As New List(Of Task)()
      Dim urls() As String = { "www.adatum.com", "www.cohovineyard.com",
                              "www.cohowinery.com", "www.northwindtraders.com",
                              "www.contoso.com" }
      
      For Each value In urls
         Dim url As String = value
         tasks.Add(Task.Run( Sub()
                                Dim png As New Ping()
                                Try
                                   Dim reply = png.Send(url)
                                   If Not reply.Status = IPStatus.Success Then
                                      Interlocked.Increment(failed)
                                      Throw New TimeoutException("Unable to reach " + url + ".")
                                   End If
                                   Catch e As PingException
                                      Interlocked.Increment(failed)
                                      Throw
                                   End Try
                             End Sub))
      Next
      Dim t As Task = Task.WhenAll(tasks)
      Try
         t.Wait()
      Catch
      End Try   

      If t.Status = TaskStatus.RanToCompletion
         Console.WriteLine("All ping attempts succeeded.")
      ElseIf t.Status = TaskStatus.Faulted
         Console.WriteLine("{0} ping attempts failed", failed)      
      End If
   End Sub
End Module
' The example displays output like the following:
'     5 ping attempts failed

注釈

オーバー ロード、WhenAllを返すメソッドをTask関心がある一連のタスクの状態または一連のタスクによってスローされた例外と、オブジェクトは通常と呼ばれます。The overloads of the WhenAll method that return a Task object are typically called when you are interested in the status of a set of tasks or in the exceptions thrown by a set of tasks.

注意

呼び出しWhenAll(IEnumerable<Task>)メソッドが呼び出し元のスレッドをブロックしません。The call to WhenAll(IEnumerable<Task>) method does not block the calling thread.

エラーが発生した状態でいずれかの指定されたタスクが完了すると、返されたタスクはでも完了、Faulted状態、その例外がラップされていない例外からの指定されたタスクのそれぞれのセットの集計に含まれています。If any of the supplied tasks completes in a faulted state, the returned task will also complete in a Faulted state, where its exceptions will contain the aggregation of the set of unwrapped exceptions from each of the supplied tasks.

指定されたタスクのエラーが発生しましたが少なくとも 1 つが取り消された場合は、返されたタスクが終了、Canceled状態。If none of the supplied tasks faulted but at least one of them was canceled, the returned task will end in the Canceled state.

結果のタスクのタスクに障害が発生してタスクが取り消された場合は、終了、RanToCompletion状態。If none of the tasks faulted and none of the tasks were canceled, the resulting task will end in the RanToCompletion state.

返されたタスクはすぐに移行する場合は、指定された配列/列挙型が含まれていないタスクには、RanToCompletion状態に、呼び出し元に返されます。If the supplied array/enumerable contains no tasks, the returned task will immediately transition to a RanToCompletion state before it's returned to the caller.

WhenAll(Task[]) WhenAll(Task[]) WhenAll(Task[]) WhenAll(Task[])

配列内のすべての Task オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task objects in an array have completed.

public:
 static System::Threading::Tasks::Task ^ WhenAll(... cli::array <System::Threading::Tasks::Task ^> ^ tasks);
public static System.Threading.Tasks.Task WhenAll (params System.Threading.Tasks.Task[] tasks);
static member WhenAll : System.Threading.Tasks.Task[] -> System.Threading.Tasks.Task
Public Shared Function WhenAll (ParamArray tasks As Task()) As Task

パラメーター

tasks
Task[]

完了を待機するタスク。The tasks to wait on for completion.

戻り値

指定されたすべてのタスクの完了を表すタスク。A task that represents the completion of all of the supplied tasks.

例外

tasks 引数が null でした。The tasks argument was null.

tasks 配列に null タスクが含まれていました。The tasks array contained a null task.

次の例では、配列内の Url に ping を実行するタスクのセットを作成します。The following example creates a set of tasks that ping the URLs in an array. タスクが格納されている、List<Task>コレクションを配列に変換されに渡される、WhenAll(IEnumerable<Task>)メソッド。The tasks are stored in a List<Task> collection that is converted to an array and passed to the WhenAll(IEnumerable<Task>) method. 呼び出し後、Waitメソッドにより、すべてのスレッドが完了した例では、検査、Task.Statusプロパティをすべてのタスクに障害が発生しているかどうかを判断します。After the call to the Wait method ensures that all threads have completed, the example examines the Task.Status property to determine whether any tasks have faulted.

using System;
using System.Collections.Generic;
using System.Net.NetworkInformation;
using System.Threading;
using System.Threading.Tasks;

public class Example
{
   public static async Task Main()
   {
      int failed = 0;
      var tasks = new List<Task>();
      String[] urls = { "www.adatum.com", "www.cohovineyard.com",
                        "www.cohowinery.com", "www.northwindtraders.com",
                        "www.contoso.com" };
      
      foreach (var value in urls) {
         var url = value;
         tasks.Add(Task.Run( () => { var png = new Ping();
                                     try {
                                        var reply = png.Send(url);
                                        if (! (reply.Status == IPStatus.Success)) {
                                           Interlocked.Increment(ref failed);
                                           throw new TimeoutException("Unable to reach " + url + ".");
                                        }
                                     }
                                     catch (PingException) {
                                        Interlocked.Increment(ref failed);
                                        throw;
                                     }
                                   }));
      }
      Task t = Task.WhenAll(tasks.ToArray());
      try {
         await t;
      }
      catch {}   

      if (t.Status == TaskStatus.RanToCompletion)
         Console.WriteLine("All ping attempts succeeded.");
      else if (t.Status == TaskStatus.Faulted)
         Console.WriteLine("{0} ping attempts failed", failed);      
   }
}
// The example displays output like the following:
//       5 ping attempts failed
Imports System.Collections.Generic
Imports System.Net.NetworkInformation
Imports System.Threading
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim failed As Integer = 0
      Dim tasks As New List(Of Task)()
      Dim urls() As String = { "www.adatum.com", "www.cohovineyard.com",
                              "www.cohowinery.com", "www.northwindtraders.com",
                              "www.contoso.com" }
      
      For Each value In urls
         Dim url As String = value
         tasks.Add(Task.Run( Sub()
                                Dim png As New Ping()
                                Try
                                   Dim reply = png.Send(url)
                                   If Not reply.Status = IPStatus.Success Then
                                      Interlocked.Increment(failed)
                                      Throw New TimeoutException("Unable to reach " + url + ".")
                                   End If
                                   Catch e As PingException
                                      Interlocked.Increment(failed)
                                      Throw
                                   End Try
                             End Sub))
      Next
      Dim t As Task = Task.WhenAll(tasks.ToArray())
      Try
         t.Wait()
      Catch
      End Try   

      If t.Status = TaskStatus.RanToCompletion
         Console.WriteLine("All ping attempts succeeded.")
      ElseIf t.Status = TaskStatus.Faulted
         Console.WriteLine("{0} ping attempts failed", failed)      
      End If
   End Sub
End Module
' The example displays output like the following:
'     5 ping attempts failed

注釈

オーバー ロード、WhenAllを返すメソッドをTask関心がある一連のタスクの状態または一連のタスクによってスローされた例外と、オブジェクトは通常と呼ばれます。The overloads of the WhenAll method that return a Task object are typically called when you are interested in the status of a set of tasks or in the exceptions thrown by a set of tasks.

注意

呼び出しWhenAll(Task[])メソッドが呼び出し元のスレッドをブロックしません。The call to WhenAll(Task[]) method does not block the calling thread.

エラーが発生した状態でいずれかの指定されたタスクが完了すると、返されたタスクはでも完了、Faulted状態、その例外がラップされていない例外からの指定されたタスクのそれぞれのセットの集計に含まれています。If any of the supplied tasks completes in a faulted state, the returned task will also complete in a Faulted state, where its exceptions will contain the aggregation of the set of unwrapped exceptions from each of the supplied tasks.

指定されたタスクのエラーが発生しましたが少なくとも 1 つが取り消された場合は、返されたタスクが終了、Canceled状態。If none of the supplied tasks faulted but at least one of them was canceled, the returned task will end in the Canceled state.

結果のタスクのタスクに障害が発生してタスクが取り消された場合は、終了、RanToCompletion状態。If none of the tasks faulted and none of the tasks were canceled, the resulting task will end in the RanToCompletion state.

返されたタスクはすぐに移行する場合は、指定された配列/列挙型が含まれていないタスクには、RanToCompletion状態に、呼び出し元に返されます。If the supplied array/enumerable contains no tasks, the returned task will immediately transition to a RanToCompletion state before it's returned to the caller.

WhenAll<TResult>(IEnumerable<Task<TResult>>) WhenAll<TResult>(IEnumerable<Task<TResult>>) WhenAll<TResult>(IEnumerable<Task<TResult>>) WhenAll<TResult>(IEnumerable<Task<TResult>>)

列挙可能なコレクション内のすべての Task<TResult> オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task<TResult> objects in an enumerable collection have completed.

public:
generic <typename TResult>
 static System::Threading::Tasks::Task<cli::array <TResult> ^> ^ WhenAll(System::Collections::Generic::IEnumerable<System::Threading::Tasks::Task<TResult> ^> ^ tasks);
public static System.Threading.Tasks.Task<TResult[]> WhenAll<TResult> (System.Collections.Generic.IEnumerable<System.Threading.Tasks.Task<TResult>> tasks);
static member WhenAll : seq<System.Threading.Tasks.Task<'Result>> -> System.Threading.Tasks.Task<'Result[]>
Public Shared Function WhenAll(Of TResult) (tasks As IEnumerable(Of Task(Of TResult))) As Task(Of TResult())

型パラメーター

TResult

完了したタスクの型。The type of the completed task.

パラメーター

tasks
IEnumerable<Task<TResult>>

完了を待機するタスク。The tasks to wait on for completion.

戻り値

Task<TResult[]>

指定されたすべてのタスクの完了を表すタスク。A task that represents the completion of all of the supplied tasks.

例外

tasks 引数が null でした。The tasks argument was null.

tasks コレクションに null タスクが含まれていました。The tasks collection contained a null task.

次の例では、それぞれを 1 ~ 1,000 で 1,000 のランダムな数値を作成しての平均を計算する乱数ジェネレーターをインスタンス化、10 個のタスクを作成します。The following example creates ten tasks, each of which instantiates a random number generator that creates 1,000 random numbers between 1 and 1,000 and computes their mean. Delay(Int32)メソッドを使用する乱数ジェネレーターのインスタンス化を遅延できるように、同一のシード値では作成されません。The Delay(Int32) method is used to delay instantiation of the random number generators so that they are not created with identical seed values. 呼び出し、WhenAllメソッド、Int64各タスクによって計算された平均値を格納している配列。The call to the WhenAll method then returns an Int64 array that contains the mean computed by each task. これらは、全体の平均を計算に使用されます。These are then used to calculate the overall mean.

using System;
using System.Collections.Generic;
using System.Threading.Tasks;

public class Example
{
   public static void Main()
   {
      var tasks = new List<Task<long>>();
      for (int ctr = 1; ctr <= 10; ctr++) {
         int delayInterval = 18 * ctr;
         tasks.Add(Task.Run(async () => { long total = 0;
                                          await Task.Delay(delayInterval);
                                          var rnd = new Random();
                                          // Generate 1,000 random numbers.
                                          for (int n = 1; n <= 1000; n++)
                                             total += rnd.Next(0, 1000);
                                          return total; } ));
      }
      var continuation = Task.WhenAll(tasks);
      try {
         continuation.Wait();
      }
      catch (AggregateException)
      { }
   
      if (continuation.Status == TaskStatus.RanToCompletion) {
         long grandTotal = 0;
         foreach (var result in continuation.Result) {
            grandTotal += result;
            Console.WriteLine("Mean: {0:N2}, n = 1,000", result/1000.0);
         }
   
         Console.WriteLine("\nMean of Means: {0:N2}, n = 10,000",
                           grandTotal/10000);
      }
      // Display information on faulted tasks.
      else {
         foreach (var t in tasks) {
            Console.WriteLine("Task {0}: {1}", t.Id, t.Status);
         }
      }
   }
}
// The example displays output like the following:
//       Mean: 506.34, n = 1,000
//       Mean: 504.69, n = 1,000
//       Mean: 489.32, n = 1,000
//       Mean: 505.96, n = 1,000
//       Mean: 515.31, n = 1,000
//       Mean: 499.94, n = 1,000
//       Mean: 496.92, n = 1,000
//       Mean: 508.58, n = 1,000
//       Mean: 494.88, n = 1,000
//       Mean: 493.53, n = 1,000
//
//       Mean of Means: 501.55, n = 10,000
Imports System.Collections.Generic
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim tasks As New List(Of Task(Of Long))()
      For ctr As Integer = 1 To 10
         Dim delayInterval As Integer = 18 * ctr
         tasks.Add(Task.Run(Async Function()
                               Dim total As Long = 0
                               Await Task.Delay(delayInterval)
                               Dim rnd As New Random()
                               ' Generate 1,000 random numbers.
                               For n As Integer = 1 To 1000
                                  total += rnd.Next(0, 1000)
                               Next
                               Return total
                            End Function))
      Next
      Dim continuation = Task.WhenAll(tasks)
      Try
         continuation.Wait()
      Catch ae As AggregateException
      End Try
      
      If continuation.Status = TaskStatus.RanToCompletion Then
         Dim grandTotal As Long = 0
         For Each result in continuation.Result
            grandTotal += result
            Console.WriteLine("Mean: {0:N2}, n = 1,000", result/1000)
         Next
         Console.WriteLine()
         Console.WriteLine("Mean of Means: {0:N2}, n = 10,000",
                           grandTotal/10000)
      ' Display information on faulted tasks.
      Else 
         For Each t In tasks
            Console.WriteLine("Task {0}: {1}", t.Id, t.Status)
         Next
      End If
   End Sub
End Module
' The example displays output like the following:
'       Mean: 506.34, n = 1,000
'       Mean: 504.69, n = 1,000
'       Mean: 489.32, n = 1,000
'       Mean: 505.96, n = 1,000
'       Mean: 515.31, n = 1,000
'       Mean: 499.94, n = 1,000
'       Mean: 496.92, n = 1,000
'       Mean: 508.58, n = 1,000
'       Mean: 494.88, n = 1,000
'       Mean: 493.53, n = 1,000
'
'       Mean of Means: 501.55, n = 10,000

ここでは、10 個の個別のタスクに格納されます、List<T>オブジェクト。In this case, the ten individual tasks are stored in a List<T> object. List<T> は、IEnumerable<T> インターフェイスを実装します。List<T> implements the IEnumerable<T> interface.

注釈

呼び出しWhenAll<TResult>(IEnumerable<Task<TResult>>)メソッドが呼び出し元のスレッドをブロックしません。The call to WhenAll<TResult>(IEnumerable<Task<TResult>>) method does not block the calling thread. ただし、呼び出し、返されたResultプロパティは、呼び出し元スレッドをブロックします。However, a call to the returned Result property does block the calling thread.

エラーが発生した状態でいずれかの指定されたタスクが完了すると、返されたタスクはでも完了、Faulted状態、その例外がラップされていない例外からの指定されたタスクのそれぞれのセットの集計に含まれています。If any of the supplied tasks completes in a faulted state, the returned task will also complete in a Faulted state, where its exceptions will contain the aggregation of the set of unwrapped exceptions from each of the supplied tasks.

指定されたタスクのエラーが発生しましたが少なくとも 1 つが取り消された場合は、返されたタスクが終了、Canceled状態。If none of the supplied tasks faulted but at least one of them was canceled, the returned task will end in the Canceled state.

結果のタスクのタスクに障害が発生してタスクが取り消された場合は、終了、RanToCompletion状態。If none of the tasks faulted and none of the tasks were canceled, the resulting task will end in the RanToCompletion state. Task<TResult>.Result返されたタスクのプロパティが指定されているすべてのと同じ順序で指定されたタスクの結果を含む配列に設定されます (例: 場合は、入力タスクに含まれている配列 t1、t2、t3、出力タスクのTask<TResult>.Resultプロパティを返しますTResult[]場所arr[0] == t1.Result, arr[1] == t2.Result, and arr[2] == t3.Result)します。The Task<TResult>.Result property of the returned task will be set to an array containing all of the results of the supplied tasks in the same order as they were provided (e.g. if the input tasks array contained t1, t2, t3, the output task's Task<TResult>.Result property will return an TResult[] where arr[0] == t1.Result, arr[1] == t2.Result, and arr[2] == t3.Result).

場合、tasks引数にタスクが含まれていない、返されたタスクはすぐに移行する、RanToCompletion状態に、呼び出し元に返されます。If the tasks argument contains no tasks, the returned task will immediately transition to a RanToCompletion state before it's returned to the caller. 返されたTResult[]0 要素の配列になります。The returned TResult[] will be an array of 0 elements.

WhenAll<TResult>(Task<TResult>[]) WhenAll<TResult>(Task<TResult>[]) WhenAll<TResult>(Task<TResult>[]) WhenAll<TResult>(Task<TResult>[])

配列内のすべての Task<TResult> オブジェクトが完了したときに完了するタスクを作成します。Creates a task that will complete when all of the Task<TResult> objects in an array have completed.

public:
generic <typename TResult>
 static System::Threading::Tasks::Task<cli::array <TResult> ^> ^ WhenAll(... cli::array <System::Threading::Tasks::Task<TResult> ^> ^ tasks);
public static System.Threading.Tasks.Task<TResult[]> WhenAll<TResult> (params System.Threading.Tasks.Task<TResult>[] tasks);
static member WhenAll : System.Threading.Tasks.Task<'Result>[] -> System.Threading.Tasks.Task<'Result[]>
Public Shared Function WhenAll(Of TResult) (ParamArray tasks As Task(Of TResult)()) As Task(Of TResult())

型パラメーター

TResult

完了したタスクの型。The type of the completed task.

パラメーター

tasks
Task<TResult>[]

完了を待機するタスク。The tasks to wait on for completion.

戻り値

Task<TResult[]>

指定されたすべてのタスクの完了を表すタスク。A task that represents the completion of all of the supplied tasks.

例外

tasks 引数が null でした。The tasks argument was null.

tasks 配列に null タスクが含まれていました。The tasks array contained a null task.

次の例では、それぞれを 1 ~ 1,000 で 1,000 のランダムな数値を作成しての平均を計算する乱数ジェネレーターをインスタンス化、10 個のタスクを作成します。The following example creates ten tasks, each of which instantiates a random number generator that creates 1,000 random numbers between 1 and 1,000 and computes their mean. ここでは、10 個の個別のタスクに格納されます、Task<Int64>配列。In this case, the ten individual tasks are stored in a Task<Int64> array. Delay(Int32)メソッドを使用する乱数ジェネレーターのインスタンス化を遅延できるように、同一のシード値では作成されません。The Delay(Int32) method is used to delay instantiation of the random number generators so that they are not created with identical seed values. 呼び出し、WhenAllメソッド、Int64各タスクによって計算された平均値を格納している配列。The call to the WhenAll method then returns an Int64 array that contains the mean computed by each task. これらは、全体の平均を計算に使用されます。These are then used to calculate the overall mean.

using System;
using System.Collections.Generic;
using System.Threading.Tasks;

public class Example
{
   public static void Main()
   {
      var tasks = new Task<long>[10];
      for (int ctr = 1; ctr <= 10; ctr++) {
         int delayInterval = 18 * ctr;
         tasks[ctr - 1] = Task.Run(async () => { long total = 0;
                                                 await Task.Delay(delayInterval);
                                                 var rnd = new Random();
                                                 // Generate 1,000 random numbers.
                                                 for (int n = 1; n <= 1000; n++)
                                                    total += rnd.Next(0, 1000);

                                                 return total; } );
      }
      var continuation = Task.WhenAll(tasks);
      try {
         continuation.Wait();
      }
      catch (AggregateException)
      {}
   
      if (continuation.Status == TaskStatus.RanToCompletion) {
         long grandTotal = 0;
         foreach (var result in continuation.Result) {
            grandTotal += result;
            Console.WriteLine("Mean: {0:N2}, n = 1,000", result/1000.0);
         }
   
         Console.WriteLine("\nMean of Means: {0:N2}, n = 10,000",
                           grandTotal/10000);
      }
      // Display information on faulted tasks.
      else { 
         foreach (var t in tasks)
            Console.WriteLine("Task {0}: {1}", t.Id, t.Status);
      }
   
   }
}
// The example displays output like the following:
//       Mean: 506.38, n = 1,000
//       Mean: 501.01, n = 1,000
//       Mean: 505.36, n = 1,000
//       Mean: 492.00, n = 1,000
//       Mean: 508.36, n = 1,000
//       Mean: 503.99, n = 1,000
//       Mean: 504.95, n = 1,000
//       Mean: 508.58, n = 1,000
//       Mean: 490.23, n = 1,000
//       Mean: 501.59, n = 1,000
//
//       Mean of Means: 502.00, n = 10,000
Imports System.Collections.Generic
Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim tasks(9) As Task(Of Long)
      For ctr As Integer = 1 To 10
         Dim delayInterval As Integer = 18 * ctr
         tasks(ctr - 1) =Task.Run(Async Function()
                                     Dim total As Long = 0
                                     Await Task.Delay(delayInterval)
                                     Dim rnd As New Random()
                                     ' Generate 1,000 random numbers.
                                     For n As Integer = 1 To 1000
                                        total += rnd.Next(0, 1000)
                                     Next
                                     Return total
                                  End Function)
      Next
      Dim continuation = Task.WhenAll(tasks)
      Try
         continuation.Wait()
      Catch ae As AggregateException
      End Try
         
      If continuation.Status = TaskStatus.RanToCompletion Then
         Dim grandTotal As Long = 0
         For Each result in continuation.Result
            grandTotal += result
            Console.WriteLine("Mean: {0:N2}, n = 1,000", result/1000)
         Next
         Console.WriteLine()
         Console.WriteLine("Mean of Means: {0:N2}, n = 10,000",
                           grandTotal/10000)
      ' Display information on faulted tasks.
      Else 
         For Each t In tasks
            Console.WriteLine("Task {0}: {1}", t.Id, t.Status)
         Next
      End If
   End Sub
End Module
' The example displays output like the following:
'       Mean: 506.38, n = 1,000
'       Mean: 501.01, n = 1,000
'       Mean: 505.36, n = 1,000
'       Mean: 492.00, n = 1,000
'       Mean: 508.36, n = 1,000
'       Mean: 503.99, n = 1,000
'       Mean: 504.95, n = 1,000
'       Mean: 508.58, n = 1,000
'       Mean: 490.23, n = 1,000
'       Mean: 501.59, n = 1,000
'
'       Mean of Means: 502.00, n = 10,000

注釈

呼び出しWhenAll<TResult>(Task<TResult>[])メソッドが呼び出し元のスレッドをブロックしません。The call to WhenAll<TResult>(Task<TResult>[]) method does not block the calling thread. ただし、呼び出し、返されたResultプロパティは、呼び出し元スレッドをブロックします。However, a call to the returned Result property does block the calling thread.

エラーが発生した状態でいずれかの指定されたタスクが完了すると、返されたタスクはでも完了、Faulted状態、その例外がラップされていない例外からの指定されたタスクのそれぞれのセットの集計に含まれています。If any of the supplied tasks completes in a faulted state, the returned task will also complete in a Faulted state, where its exceptions will contain the aggregation of the set of unwrapped exceptions from each of the supplied tasks.

指定されたタスクのエラーが発生しましたが少なくとも 1 つが取り消された場合は、返されたタスクが終了、Canceled状態。If none of the supplied tasks faulted but at least one of them was canceled, the returned task will end in the Canceled state.

結果のタスクのタスクに障害が発生してタスクが取り消された場合は、終了、RanToCompletion状態。If none of the tasks faulted and none of the tasks were canceled, the resulting task will end in the RanToCompletion state. Resultの返されたタスクが指定されているすべてのと同じ順序で指定されたタスクの結果を含む配列に設定されます (例: 場合は、入力タスクに含まれている配列 t1、t2、t3、出力タスクのResultが返されます、 TResult[]場所arr[0] == t1.Result, arr[1] == t2.Result, and arr[2] == t3.Result)します。The Result of the returned task will be set to an array containing all of the results of the supplied tasks in the same order as they were provided (e.g. if the input tasks array contained t1, t2, t3, the output task's Result will return an TResult[] where arr[0] == t1.Result, arr[1] == t2.Result, and arr[2] == t3.Result).

返されたタスクはすぐに移行する場合は、指定された配列/列挙型が含まれていないタスクには、RanToCompletion状態に、呼び出し元に返されます。If the supplied array/enumerable contains no tasks, the returned task will immediately transition to a RanToCompletion state before it's returned to the caller. 返されたTResult[]0 要素の配列になります。The returned TResult[] will be an array of 0 elements.

適用対象