Task.WaitAll Método

Aguarda até que todos os objetos Task fornecidos tenham concluído a execução.Waits for all of the provided Task objects to complete execution.

public:
 static void WaitAll(... cli::array <System::Threading::Tasks::Task ^> ^ tasks);

public static void WaitAll (params System.Threading.Tasks.Task[] tasks);

static member WaitAll : System.Threading.Tasks.Task[] -> unit

Public Shared Sub WaitAll (ParamArray tasks As Task())

Parâmetros

Exceções

Exemplos

O exemplo a seguir inicia 10 tarefas, sendo que cada uma passa um índice como um objeto de estado.The following example starts 10 tasks, each of which is passed an index as a state object. As tarefas com um índice de duas a cinco geram exceções.Tasks with an index from two to five throw exceptions. A chamada para o método WaitAll encapsula todas as exceções em um objeto AggregateException e a propaga para o thread de chamada.The call to the WaitAll method wraps all exceptions in an AggregateException object and propagates it to the calling thread.

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

class Example
{
    static void Main()
    {
        var tasks = new List<Task<int>>();
         
        // Define a delegate that prints and returns the system tick count
        Func<object, int> action = (object obj) =>
        {
            int i = (int)obj;

            // Make each thread sleep a different time in order to return a different tick count
            Thread.Sleep(i * 100);

            // The tasks that receive an argument between 2 and 5 throw exceptions
            if (2 <= i && i <= 5)
            {
                throw new InvalidOperationException("SIMULATED EXCEPTION");
            }

            int tickCount = Environment.TickCount;
            Console.WriteLine("Task={0}, i={1}, TickCount={2}, Thread={3}", Task.CurrentId, i, tickCount, Thread.CurrentThread.ManagedThreadId);

            return tickCount;
        };

        // Construct started tasks
        for (int i = 0; i < 10; i++)
        {
            int index = i;
            tasks.Add(Task<int>.Factory.StartNew(action, index));
        }

        try
        {
            // Wait for all the tasks to finish.
            Task.WaitAll(tasks.ToArray());

            // We should never get to this point
            Console.WriteLine("WaitAll() has not thrown exceptions. THIS WAS NOT EXPECTED.");
        }
        catch (AggregateException e)
        {
            Console.WriteLine("\nThe following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)");
            for (int j = 0; j < e.InnerExceptions.Count; j++)
            {
                Console.WriteLine("\n-------------------------------------------------\n{0}", e.InnerExceptions[j].ToString());
            }
        }
    }
}
// The example displays output like the following:
//     Task=1, i=0, TickCount=1203822250, Thread=3
//     Task=2, i=1, TickCount=1203822359, Thread=4
//     Task=7, i=6, TickCount=1203823484, Thread=3
//     Task=8, i=7, TickCount=1203823890, Thread=4
//     Task=9, i=8, TickCount=1203824296, Thread=3
//     Task=10, i=9, TickCount=1203824796, Thread=4
//     
//     The following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()
//     
//     -------------------------------------------------
//     System.InvalidOperationException: SIMULATED EXCEPTION
//        at Example.<Main>b__0(Object obj)
//        at System.Threading.Tasks.Task`1.InnerInvoke()
//        at System.Threading.Tasks.Task.Execute()

Imports System.Collections.Generic
Imports System.Threading
Imports System.Threading.Tasks

Module WaitAllDemo
    Sub Main()
        Dim tasks As New List(Of Task(Of Integer))()
        ' Define a delegate that prints and returns the system tick count
        Dim action As Func(Of Object, Integer) = Function(obj As Object)
                                                     Dim i As Integer = CInt(obj)

                                                     ' Make each thread sleep a different time in order to return a different tick count
                                                     Thread.Sleep(i * 100)

                                                     ' The tasks that receive an argument between 2 and 5 throw exceptions
                                                     If 2 <= i AndAlso i <= 5 Then
                                                         Throw New InvalidOperationException("SIMULATED EXCEPTION")
                                                     End If

                                                     Dim tickCount As Integer = Environment.TickCount
                                                     Console.WriteLine("Task={0}, i={1}, TickCount={2}, Thread={3}", Task.CurrentId, i, tickCount, Thread.CurrentThread.ManagedThreadId)

                                                     Return tickCount
                                                 End Function

        ' Construct started tasks
        For i As Integer = 0 To 9
            Dim index As Integer = i
            tasks.Add(Task(Of Integer).Factory.StartNew(action, index))
        Next

        Try
            ' Wait for all the tasks to finish.
            Task.WaitAll(tasks.ToArray())

            ' We should never get to this point
            Console.WriteLine("WaitAll() has not thrown exceptions. THIS WAS NOT EXPECTED.")
        Catch e As AggregateException
            Console.WriteLine(vbLf & "The following exceptions have been thrown by WaitAll(): (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
' The example displays output like the following:
'     Task=1, i=0, TickCount=1203822250, Thread=3
'     Task=2, i=1, TickCount=1203822359, Thread=4
'     Task=7, i=6, TickCount=1203823484, Thread=3
'     Task=8, i=7, TickCount=1203823890, Thread=4
'     Task=9, i=8, TickCount=1203824296, Thread=3
'     Task=10, i=9, TickCount=1203824796, Thread=4
'     
'     The following exceptions have been thrown by WaitAll(): (THIS WAS EXPECTED)
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()
'     
'     -------------------------------------------------
'     System.InvalidOperationException: SIMULATED EXCEPTION
'        at Example.<Main>b__0(Object obj)
'        at System.Threading.Tasks.Task`1.InnerInvoke()
'        at System.Threading.Tasks.Task.Execute()

Aguarda todos os objetos Task fornecidos concluírem a execução dentro de um número especificado de milissegundos.Waits for all of the provided Task objects to complete execution within a specified number of milliseconds.

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, int millisecondsTimeout);

public static bool WaitAll (System.Threading.Tasks.Task[] tasks, int millisecondsTimeout);

static member WaitAll : System.Threading.Tasks.Task[] * int -> bool

Public Shared Function WaitAll (tasks As Task(), millisecondsTimeout As Integer) As Boolean

Parâmetros

Retornos

Exceções

Aguarda até que todos os objetos Task fornecidos tenham concluído a execução, a menos que a espera seja cancelada.Waits for all of the provided Task objects to complete execution unless the wait is cancelled.

public:
 static void WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, System::Threading::CancellationToken cancellationToken);

public static void WaitAll (System.Threading.Tasks.Task[] tasks, System.Threading.CancellationToken cancellationToken);

static member WaitAll : System.Threading.Tasks.Task[] * System.Threading.CancellationToken -> unit

Parâmetros

Exceções

Comentários

O argumento cancellationToken é usado para cancelar a operação de espera.The cancellationToken argument is used to cancel the wait operation. O cancelamento das tarefas é uma operação distinta e é sinalizado pelo AggregateException conforme indicado acima.Cancellation of the tasks is a distinct operation, and is signaled by the AggregateException as noted above.

Aguarda todos os objetos Task canceláveis fornecidos concluírem a execução dentro de um intervalo de tempo especificado.Waits for all of the provided cancellable Task objects to complete execution within a specified time interval.

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, TimeSpan timeout);

public static bool WaitAll (System.Threading.Tasks.Task[] tasks, TimeSpan timeout);

static member WaitAll : System.Threading.Tasks.Task[] * TimeSpan -> bool

Public Shared Function WaitAll (tasks As Task(), timeout As TimeSpan) As Boolean

Parâmetros

Retornos

Exceções

Aguarda todos os objetos Task fornecidos concluírem a execução em um número especificado de milissegundos ou até que a espera seja cancelada.Waits for all of the provided Task objects to complete execution within a specified number of milliseconds or until the wait is cancelled.

public:
 static bool WaitAll(cli::array <System::Threading::Tasks::Task ^> ^ tasks, int millisecondsTimeout, System::Threading::CancellationToken cancellationToken);

public static bool WaitAll (System.Threading.Tasks.Task[] tasks, int millisecondsTimeout, System.Threading.CancellationToken cancellationToken);

static member WaitAll : System.Threading.Tasks.Task[] * int * System.Threading.CancellationToken -> bool

Parâmetros

Retornos

Exceções

Comentários

O argumento cancellationToken é usado para cancelar a operação de espera.The cancellationToken argument is used to cancel the wait operation. O cancelamento das tarefas é uma operação distinta e é sinalizado pelo AggregateException observado acima.Cancellation of the tasks is a distinct operation, and is signaled by the AggregateException noted above.