ThreadAbortException Classe

Definição

public ref class ThreadAbortException sealed : SystemException

[System.Serializable]
public sealed class ThreadAbortException : SystemException

[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class ThreadAbortException : SystemException

public sealed class ThreadAbortException : SystemException

[<System.Serializable>]
type ThreadAbortException = class
    inherit SystemException

[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type ThreadAbortException = class
    inherit SystemException

type ThreadAbortException = class
    inherit SystemException

Public NotInheritable Class ThreadAbortException
Inherits SystemException

Herança

Object

Exception

SystemException

ThreadAbortException

Atributos

SerializableAttribute ComVisibleAttribute

Exemplos

O exemplo seguinte demonstra a anulação de um thread. A thread que recebe o ThreadAbortException utiliza o ResetAbort método para cancelar o pedido de aborto e continuar a executar.

using System;
using System.Threading;
using System.Security.Permissions;

public class ThreadWork {
    public static void DoWork() {
        try {
            for(int i=0; i<100; i++) {
                Console.WriteLine("Thread - working.");
                Thread.Sleep(100);
            }
        }
        catch(ThreadAbortException e) {
            Console.WriteLine("Thread - caught ThreadAbortException - resetting.");
            Console.WriteLine("Exception message: {0}", e.Message);
            Thread.ResetAbort();
        }
        Console.WriteLine("Thread - still alive and working.");
        Thread.Sleep(1000);
        Console.WriteLine("Thread - finished working.");
    }
}

class ThreadAbortTest {
    public static void Main() {
        ThreadStart myThreadDelegate = new ThreadStart(ThreadWork.DoWork);
        Thread myThread = new Thread(myThreadDelegate);
        myThread.Start();
        Thread.Sleep(100);
        Console.WriteLine("Main - aborting my thread.");
        myThread.Abort();
        myThread.Join();
        Console.WriteLine("Main ending.");
    }
}

Imports System.Threading
Imports System.Security.Permissions


Public Class ThreadWork
   Public Shared Sub DoWork()
      Try
         Dim i As Integer
         For i = 0 To 99
            Console.WriteLine("Thread - working.")
            Thread.Sleep(100)
         Next i
      Catch e As ThreadAbortException
         Console.WriteLine("Thread - caught ThreadAbortException - resetting.")
         Console.WriteLine("Exception message: {0}", e.Message)
         Thread.ResetAbort()
      End Try
      Console.WriteLine("Thread - still alive and working.")
      Thread.Sleep(1000)
      Console.WriteLine("Thread - finished working.")
   End Sub
End Class


Class ThreadAbortTest
   Public Shared Sub Main()
      Dim myThreadDelegate As New ThreadStart(AddressOf ThreadWork.DoWork)
      Dim myThread As New Thread(myThreadDelegate)
      myThread.Start()
      Thread.Sleep(100)
      Console.WriteLine("Main - aborting my thread.")
      myThread.Abort()
      myThread.Join()
      Console.WriteLine("Main ending.")
   End Sub
End Class

Este código gera o seguinte resultado:

Thread - working.
Main - aborting my thread.
Thread - caught ThreadAbortException - resetting.
Exception message: Thread was being aborted.
Thread - still alive and working.
Thread - finished working.
Main ending.

Observações

Quando é feita uma chamada ao método Abort para destruir um thread, o runtime da linguagem comum lança um ThreadAbortException no .NET Framework. ThreadAbortException é uma exceção especial que pode ser apanhada, mas será automaticamente levantada novamente no final do catch bloco. Quando esta exceção é levantada, o tempo de execução executa todos os blocos finally antes de terminar a thread. Como o thread pode fazer um cálculo ilimitado nos finally blocos ou chamar Thread.ResetAbort para cancelar o abort, não há garantia de que o thread alguma vez termine. Se quiseres esperar até que o thread abortado termine, podes chamar o Thread.Join método. Join é uma chamada de bloqueio que só retorna até que o thread pare efetivamente de executar.

ThreadAbortException usa HRESULT COR_E_THREADABORTED, que tem o valor 0x80131530.

Ver também

• Thread
• Abort(Object)
• Destruição de fios