TaskStatus TaskStatus TaskStatus TaskStatus Enum

Definição

Representa o estágio atual no ciclo de vida de um Task.Represents the current stage in the lifecycle of a Task.

public enum class TaskStatus
public enum TaskStatus
type TaskStatus = 
Public Enum TaskStatus
Herança

Campos

Canceled Canceled Canceled Canceled 6

A tarefa confirmou o cancelamento lançando um OperationCanceledException com seu próprio CancellationToken enquanto o token estava no estado sinalizado, ou o CancellationToken da tarefa já estava sinalizado antes do início da execução da tarefa.The task acknowledged cancellation by throwing an OperationCanceledException with its own CancellationToken while the token was in signaled state, or the task's CancellationToken was already signaled before the task started executing. Para obter mais informações, consulte Cancelamento de tarefas.For more information, see Task Cancellation.

Created Created Created Created 0

A tarefa foi inicializada, mas ainda não foi agendada.The task has been initialized but has not yet been scheduled.

Faulted Faulted Faulted Faulted 7

A tarefa foi concluída devido a uma exceção sem tratamento.The task completed due to an unhandled exception.

RanToCompletion RanToCompletion RanToCompletion RanToCompletion 5

A execução da tarefa foi concluída com êxito.The task completed execution successfully.

Running Running Running Running 3

A tarefa está em execução, mas ainda não foi concluída.The task is running but has not yet completed.

WaitingForActivation WaitingForActivation WaitingForActivation WaitingForActivation 1

A tarefa está aguardando para ser ativada e agendada internamente pela infraestrutura do .NET Framework.The task is waiting to be activated and scheduled internally by the .NET Framework infrastructure.

WaitingForChildrenToComplete WaitingForChildrenToComplete WaitingForChildrenToComplete WaitingForChildrenToComplete 4

A tarefa terminou de ser executada e está aguardando implicitamente a conclusão de tarefas filho anexadas.The task has finished executing and is implicitly waiting for attached child tasks to complete.

WaitingToRun WaitingToRun WaitingToRun WaitingToRun 2

A tarefa foi agendada para execução, mas ainda não começou a ser executada.The task has been scheduled for execution but has not yet begun executing.

Exemplos

O exemplo a seguir cria 20 tarefas que serão repetidas até que um contador seja incrementado para um valor de 2 milhões.The following example creates 20 tasks that will loop until a counter is incremented to a value of 2 million. Quando as 10 primeiras tarefas atingem 2 milhões, o token de cancelamento é cancelado e todas as tarefas cujos contadores não chegaram 2 milhões são canceladas.When the first 10 tasks reach 2 million, the cancellation token is cancelled, and any tasks whose counters have not reached 2 million are cancelled. Em seguida, o exemplo examina Task.Status a propriedade de cada tarefa para indicar se a tarefa foi concluída com êxito ou se foi cancelada.The example then examines the Task.Status property of each task to indicate whether the task has completed successfully or been cancelled. Para aqueles que foram concluídos, ele exibe o valor retornado pela tarefa.For those that have completed, it displays the value returned by the task.

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

public class Example
{
   public static void Main()
   {
      var tasks = new List<Task<int>>();
      var source = new CancellationTokenSource();
      var token = source.Token;
      int completedIterations = 0;

      for (int n = 0; n <= 19; n++)
         tasks.Add(Task.Run( () => { int iterations = 0;
                                     for (int ctr = 1; ctr <= 2000000; ctr++) {
                                         token.ThrowIfCancellationRequested();
                                         iterations++;
                                     }
                                     Interlocked.Increment(ref completedIterations);
                                     if (completedIterations >= 10)
                                        source.Cancel();
                                     return iterations; }, token));

      Console.WriteLine("Waiting for the first 10 tasks to complete...\n");
      try  {
         Task.WaitAll(tasks.ToArray());
      }
      catch (AggregateException) {
         Console.WriteLine("Status of tasks:\n");
         Console.WriteLine("{0,10} {1,20} {2,14:N0}", "Task Id",
                           "Status", "Iterations");
         foreach (var t in tasks)
            Console.WriteLine("{0,10} {1,20} {2,14}",
                              t.Id, t.Status,
                              t.Status != TaskStatus.Canceled ? t.Result.ToString("N0") : "n/a");
      }
   }
}
// The example displays output like the following:
//    Waiting for the first 10 tasks to complete...
//    Status of tasks:
//
//       Task Id               Status     Iterations
//             1      RanToCompletion      2,000,000
//             2      RanToCompletion      2,000,000
//             3      RanToCompletion      2,000,000
//             4      RanToCompletion      2,000,000
//             5      RanToCompletion      2,000,000
//             6      RanToCompletion      2,000,000
//             7      RanToCompletion      2,000,000
//             8      RanToCompletion      2,000,000
//             9      RanToCompletion      2,000,000
//            10             Canceled            n/a
//            11             Canceled            n/a
//            12             Canceled            n/a
//            13             Canceled            n/a
//            14             Canceled            n/a
//            15             Canceled            n/a
//            16      RanToCompletion      2,000,000
//            17             Canceled            n/a
//            18             Canceled            n/a
//            19             Canceled            n/a
//            20             Canceled            n/a
Imports System.Collections.Generic
Imports System.Threading
Imports System.Threading.Tasks

Module Example

   Public Sub Main()
      Dim tasks As New List(Of Task(Of Integer))()
      Dim source As New CancellationTokenSource
      Dim token As CancellationToken = source.Token
      Dim completedIterations As Integer = 0
      
      For n As Integer = 0 To 19
         tasks.Add(Task.Run( Function()
                                Dim iterations As Integer= 0
                                For ctr As Long = 1 To 2000000
                                   token.ThrowIfCancellationRequested()
                                   iterations += 1
                                Next
                                Interlocked.Increment(completedIterations)
                                If completedIterations >= 10 Then source.Cancel()
                                Return iterations
                             End Function, token))
      Next

      Console.WriteLine("Waiting for the first 10 tasks to complete... ")
      Try
         Task.WaitAll(tasks.ToArray())
      Catch e As AggregateException
         Console.WriteLine("Status of tasks:")
         Console.WriteLine()
         Console.WriteLine("{0,10} {1,20} {2,14}", "Task Id",
                           "Status", "Iterations")
         For Each t In tasks
            Console.WriteLine("{0,10} {1,20} {2,14}",
                              t.Id, t.Status,
                              If(t.Status <> TaskStatus.Canceled,
                                 t.Result.ToString("N0"), "n/a"))
         Next
      End Try
   End Sub
End Module
' The example displays output like the following:
'    Waiting for the first 10 tasks to complete...
'    Status of tasks:
'
'       Task Id               Status     Iterations
'             1      RanToCompletion      2,000,000
'             2      RanToCompletion      2,000,000
'             3      RanToCompletion      2,000,000
'             4      RanToCompletion      2,000,000
'             5      RanToCompletion      2,000,000
'             6      RanToCompletion      2,000,000
'             7      RanToCompletion      2,000,000
'             8      RanToCompletion      2,000,000
'             9      RanToCompletion      2,000,000
'            10             Canceled            n/a
'            11             Canceled            n/a
'            12             Canceled            n/a
'            13             Canceled            n/a
'            14             Canceled            n/a
'            15             Canceled            n/a
'            16      RanToCompletion      2,000,000
'            17             Canceled            n/a
'            18             Canceled            n/a
'            19             Canceled            n/a
'            20             Canceled            n/a

Comentários

A Task.Status propriedade retorna um membro TaskStatus da enumeração para indicar o status atual da tarefa.The Task.Status property returns a member of the TaskStatus enumeration to indicate the task's current status.

Aplica-se a

Veja também