Task.ContinueWith Método

Definición

Espacio de nombres:: System.Threading.Tasks

Ensamblado:: System.Threading.Tasks.dll

Ensamblado:: System.Runtime.dll

Ensamblados:: mscorlib.dll, netstandard.dll

Ensamblado:: mscorlib.dll

Ensamblado:: netstandard.dll

Crea una continuación que se ejecuta de manera asincrónica cuando se completa el objeto Task de destino.Creates a continuation that executes asynchronously when the target Task completes.

Sobrecargas

ContinueWith(Action<Task,Object>, Object, CancellationToken, TaskContinuationOptions, TaskScheduler)	Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y un token de cancelación y que se ejecuta cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and a cancellation token and that executes when the target Task completes. La continuación se ejecuta según un conjunto de condiciones especificadas y usa un programador especificado.The continuation executes based on a set of specified conditions and uses a specified scheduler.
ContinueWith(Action<Task>, CancellationToken, TaskContinuationOptions, TaskScheduler)	Crea una continuación que se ejecuta cuando se completa la tarea de destino según el elemento TaskContinuationOptions especificado.Creates a continuation that executes when the target task competes according to the specified TaskContinuationOptions. La continuación recibe un token de cancelación y usa un programador especificado.The continuation receives a cancellation token and uses a specified scheduler.
ContinueWith(Action<Task,Object>, Object, TaskScheduler)	Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y se ejecuta de forma asincrónica cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and executes asynchronously when the target Task completes. La continuación usa un programador especificado.The continuation uses a specified scheduler.
ContinueWith(Action<Task,Object>, Object, TaskContinuationOptions)	Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y se ejecuta cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and executes when the target Task completes. La continuación se ejecuta según un conjunto de condiciones especificadas.The continuation executes based on a set of specified conditions.
ContinueWith(Action<Task,Object>, Object, CancellationToken)	Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y un token de cancelación y que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and a cancellation token and that executes asynchronously when the target Task completes.
ContinueWith(Action<Task,Object>, Object)	Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y se ejecuta cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and executes when the target Task completes.
ContinueWith(Action<Task>, TaskContinuationOptions)	Crea una continuación que se ejecuta cuando se completa la tarea de destino según el elemento TaskContinuationOptions especificado.Creates a continuation that executes when the target task completes according to the specified TaskContinuationOptions.
ContinueWith(Action<Task>, CancellationToken)	Crea una continuación que recibe un token de cancelación y se ejecuta de forma asincrónica cuando el elemento Task de destino se completa.Creates a continuation that receives a cancellation token and executes asynchronously when the target Task completes.
ContinueWith(Action<Task>)	Crea una continuación que se ejecuta de manera asincrónica cuando se completa el objeto Task de destino.Creates a continuation that executes asynchronously when the target Task completes.
ContinueWith(Action<Task>, TaskScheduler)	Crea una continuación que se ejecuta de manera asincrónica cuando se completa el objeto Task de destino.Creates a continuation that executes asynchronously when the target Task completes. La continuación usa un programador especificado.The continuation uses a specified scheduler.
ContinueWith<TResult>(Func<Task,Object,TResult>, Object, TaskContinuationOptions)	Crea una continuación que se ejecuta según las opciones de continuación de la tarea especificadas cuando el elemento Task de destino se completa.Creates a continuation that executes based on the specified task continuation options when the target Task completes. La continuación recibe información de estado proporcionada por el autor de la llamada.The continuation receives caller-supplied state information.
ContinueWith<TResult>(Func<Task,Object,TResult>, Object, CancellationToken, TaskContinuationOptions, TaskScheduler)	Crea una continuación que se ejecuta según las opciones de continuación de la tarea especificadas cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes based on the specified task continuation options when the target Task completes and returns a value. La continuación recibe información de estado proporcionada por el autor de la llamada y un token de cancelación y usa el programador especificado.The continuation receives caller-supplied state information and a cancellation token and uses the specified scheduler.
ContinueWith<TResult>(Func<Task,TResult>, CancellationToken, TaskContinuationOptions, TaskScheduler)	Crea una continuación que se ejecuta según las opciones de continuación especificadas y devuelve un valor.Creates a continuation that executes according to the specified continuation options and returns a value. Se pasa un token de cancelación a la continuación y usa un programador especificado.The continuation is passed a cancellation token and uses a specified scheduler.
ContinueWith<TResult>(Func<Task,Object,TResult>, Object, TaskScheduler)	Crea una continuación que se ejecuta de manera asincrónica cuando se completa el objeto Task de destino.Creates a continuation that executes asynchronously when the target Task completes. La continuación recibe información de estado proporcionada por el autor de la llamada y usa a un programador especificado.The continuation receives caller-supplied state information and uses a specified scheduler.
ContinueWith<TResult>(Func<Task,Object,TResult>, Object, CancellationToken)	Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task completes and returns a value. La continuación recibe información de estado proporcionada por el autor de la llamada y un token de cancelación.The continuation receives caller-supplied state information and a cancellation token.
ContinueWith<TResult>(Func<Task,Object,TResult>, Object)	Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that receives caller-supplied state information and executes asynchronously when the target Task completes and returns a value.
ContinueWith<TResult>(Func<Task,TResult>, TaskContinuationOptions)	Crea una continuación que se ejecuta según las opciones de continuación especificadas y devuelve un valor.Creates a continuation that executes according to the specified continuation options and returns a value.
ContinueWith<TResult>(Func<Task,TResult>, CancellationToken)	Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task completes and returns a value. La continuación recibe un token de cancelación.The continuation receives a cancellation token.
ContinueWith<TResult>(Func<Task,TResult>, TaskScheduler)	Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task completes and returns a value. La continuación usa un programador especificado.The continuation uses a specified scheduler.
ContinueWith<TResult>(Func<Task,TResult>)	Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task<TResult> de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task<TResult> completes and returns a value.

ContinueWith(Action<Task,Object>, Object, CancellationToken, TaskContinuationOptions, TaskScheduler)

Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y un token de cancelación y que se ejecuta cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and a cancellation token and that executes when the target Task completes. La continuación se ejecuta según un conjunto de condiciones especificadas y usa un programador especificado.The continuation executes based on a set of specified conditions and uses a specified scheduler.

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^, System::Object ^> ^ continuationAction, System::Object ^ state, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskContinuationOptions continuationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object> continuationAction, object state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskContinuationOptions continuationOptions, System.Threading.Tasks.TaskScheduler scheduler);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object?> continuationAction, object? state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskContinuationOptions continuationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Action<System.Threading.Tasks.Task, obj> * obj * System.Threading.CancellationToken * System.Threading.Tasks.TaskContinuationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task, Object), state As Object, cancellationToken As CancellationToken, continuationOptions As TaskContinuationOptions, scheduler As TaskScheduler) As Task

Parámetros

continuationAction: Action<Task,Object>

Acción que se va a ejecutar cuando se complete el objeto Task.An action to run when the Task completes. Cuando se ejecute, se pasarán al delegado la tarea completada y el objeto de estado proporcionado por el llamador como argumentos.When run, the delegate will be passed the completed task and the caller-supplied state object as arguments.

state: Object

Objeto que representa los datos que la acción de continuación va a usar.An object representing data to be used by the continuation action.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

continuationOptions: TaskContinuationOptions

Opciones para la programación y el comportamiento de la continuación.Options for when the continuation is scheduled and how it behaves. Incluye criterios, como OnlyOnCanceled, y opciones de ejecución, como ExecuteSynchronously.This includes criteria, such as OnlyOnCanceled, as well as execution options, such as ExecuteSynchronously.

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ArgumentNullException

El argumento scheduler es null.The scheduler argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

ObjectDisposedException

Ya se eliminó el CancellationToken proporcionado.The provided CancellationToken has already been disposed.

Comentarios

El devuelto Task no se programará para su ejecución hasta que se complete la tarea actual.The returned Task will not be scheduled for execution until the current task has completed. Si no se cumplen los criterios especificados a través del continuationOptions parámetro, la tarea de continuación se cancelará en lugar de programar.If the criteria specified through the continuationOptions parameter are not met, the continuation task will be canceled instead of scheduled.

Se aplica a

ContinueWith(Action<Task>, CancellationToken, TaskContinuationOptions, TaskScheduler)

Crea una continuación que se ejecuta cuando se completa la tarea de destino según el elemento TaskContinuationOptions especificado.Creates a continuation that executes when the target task competes according to the specified TaskContinuationOptions. La continuación recibe un token de cancelación y usa un programador especificado.The continuation receives a cancellation token and uses a specified scheduler.

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^> ^ continuationAction, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskContinuationOptions continuationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task> continuationAction, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskContinuationOptions continuationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Action<System.Threading.Tasks.Task> * System.Threading.CancellationToken * System.Threading.Tasks.TaskContinuationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task), cancellationToken As CancellationToken, continuationOptions As TaskContinuationOptions, scheduler As TaskScheduler) As Task

Parámetros

continuationAction: Action<Task>

Una acción para ejecutarse según el continuationOptionsespecificado.An action to run according to the specified continuationOptions. Cuando se ejecute, al delegado se le pasará la tarea completada como un argumento.When run, the delegate will be passed the completed task as an argument.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

continuationOptions: TaskContinuationOptions

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ObjectDisposedException

El CancellationTokenSource que creó el token ya se ha eliminado.The CancellationTokenSource that created the token has already been disposed.

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

O bien-or- El argumento scheduler es null.The scheduler argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

Ejemplos

El siguiente es un ejemplo del uso de ContinueWith para ejecutar el trabajo en segundo plano y en los subprocesos de la interfaz de usuario.The following is an example of using ContinueWith to run work both in the background and on the user interface threads.

private void Button1_Click(object sender, EventArgs e)  
{  
   var backgroundScheduler = TaskScheduler.Default;  
   var uiScheduler = TaskScheduler.FromCurrentSynchronizationContext();  
   Task.Factory.StartNew(delegate { DoBackgroundComputation(); },  
                         backgroundScheduler).  
   ContinueWith(delegate { UpdateUI(); }, uiScheduler).  
                ContinueWith(delegate { DoAnotherBackgroundComputation(); },  
                             backgroundScheduler).  
                ContinueWith(delegate { UpdateUIAgain(); }, uiScheduler);  
}

Private Sub Button1_Click(ByVal sender As System.Object,   
                          ByVal e As System.EventArgs) Handles Button1.Click  
   Dim backgroundScheduler = TaskScheduler.Default  
   Dim uiScheduler = TaskScheduler.FromCurrentSynchronizationContext()  

   Task.Factory.StartNew(Sub()  
                           DoBackgroundComputation()  
                         End Sub, backgroundScheduler).ContinueWith(Sub(t)  
                            UpdateUI()  
                         End Sub, uiScheduler).ContinueWith(Sub(t)  
                            DoAnotherBackgroundComputation()  
                         End Sub, backgroundScheduler).ContinueWith(Sub(t)  
                            UpdateUIAgain()  
                         End Sub, uiScheduler)  
End Sub

Comentarios

Se aplica a

ContinueWith(Action<Task,Object>, Object, TaskScheduler)

Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y se ejecuta de forma asincrónica cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and executes asynchronously when the target Task completes. La continuación usa un programador especificado.The continuation uses a specified scheduler.

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^, System::Object ^> ^ continuationAction, System::Object ^ state, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object> continuationAction, object state, System.Threading.Tasks.TaskScheduler scheduler);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object?> continuationAction, object? state, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Action<System.Threading.Tasks.Task, obj> * obj * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task, Object), state As Object, scheduler As TaskScheduler) As Task

Parámetros

continuationAction: Action<Task,Object>

state: Object

Objeto que representa los datos que la acción de continuación va a usar.An object representing data to be used by the continuation action.

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ArgumentNullException

El argumento scheduler es null.The scheduler argument is null.

Comentarios

El devuelto Task no se programará para su ejecución hasta que se complete la tarea actual, si se completa debido a que la ejecución se ha completado correctamente, a que se ha producido un error debido a una excepción no controlada o a un cierre temprano debido a su cancelación.The returned Task will not be scheduled for execution until the current task has completed, whether it completes due to running to completion successfully, faulting due to an unhandled exception, or exiting out early due to being canceled.

Se aplica a

ContinueWith(Action<Task,Object>, Object, TaskContinuationOptions)

Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y se ejecuta cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and executes when the target Task completes. La continuación se ejecuta según un conjunto de condiciones especificadas.The continuation executes based on a set of specified conditions.

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^, System::Object ^> ^ continuationAction, System::Object ^ state, System::Threading::Tasks::TaskContinuationOptions continuationOptions);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object> continuationAction, object state, System.Threading.Tasks.TaskContinuationOptions continuationOptions);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object?> continuationAction, object? state, System.Threading.Tasks.TaskContinuationOptions continuationOptions);

member this.ContinueWith : Action<System.Threading.Tasks.Task, obj> * obj * System.Threading.Tasks.TaskContinuationOptions -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task, Object), state As Object, continuationOptions As TaskContinuationOptions) As Task

Parámetros

continuationAction: Action<Task,Object>

state: Object

Objeto que representa los datos que la acción de continuación va a usar.An object representing data to be used by the continuation action.

continuationOptions: TaskContinuationOptions

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

Comentarios

El devuelto Task no se programará para su ejecución hasta que se complete la tarea actual.The returned Task will not be scheduled for execution until the current task has completed. Si no se cumplen los criterios de continuación especificados a través del continuationOptions parámetro, la tarea de continuación se cancelará en lugar de programada.If the continuation criteria specified through the continuationOptions parameter are not met, the continuation task will be canceled instead of scheduled.

Se aplica a

ContinueWith(Action<Task,Object>, Object, CancellationToken)

Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y un token de cancelación y que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa.Creates a continuation that receives caller-supplied state information and a cancellation token and that executes asynchronously when the target Task completes.

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^, System::Object ^> ^ continuationAction, System::Object ^ state, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object> continuationAction, object state, System.Threading.CancellationToken cancellationToken);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object?> continuationAction, object? state, System.Threading.CancellationToken cancellationToken);

member this.ContinueWith : Action<System.Threading.Tasks.Task, obj> * obj * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task, Object), state As Object, cancellationToken As CancellationToken) As Task

Parámetros

continuationAction: Action<Task,Object>

state: Object

Objeto que representa los datos que la acción de continuación va a usar.An object representing data to be used by the continuation action.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

ObjectDisposedException

Ya se eliminó el CancellationToken proporcionado.The provided CancellationToken has already been disposed.

Comentarios

Se aplica a

ContinueWith(Action<Task,Object>, Object)

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^, System::Object ^> ^ continuationAction, System::Object ^ state);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object> continuationAction, object state);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task,object?> continuationAction, object? state);

member this.ContinueWith : Action<System.Threading.Tasks.Task, obj> * obj -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task, Object), state As Object) As Task

Parámetros

continuationAction: Action<Task,Object>

Acción que se ejecutará cuando se complete la tarea.An action to run when the task completes. Cuando se ejecuta, se pasa al delegado la tarea completada y el objeto de estado proporcionado por el autor de la llamada como argumentos.When run, the delegate is passed the completed task and a caller-supplied state object as arguments.

state: Object

Objeto que representa los datos que la acción de continuación va a usar.An object representing data to be used by the continuation action.

Devoluciones

Task

Una tarea de continuación nueva.A new continuation task.

Excepciones

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

Comentarios

El devuelto Task no se programará para su ejecución hasta que se complete la tarea actual, si se completa debido a que la ejecución se ha completado correctamente, a que se ha producido un error debido a una excepción no controlada o a una salida temprana debido a la cancelación.The returned Task will not be scheduled for execution until the current task has completed, whether it completes due to running to completion successfully, faulting due to an unhandled exception, or exiting early due to cancellation.

Se aplica a

ContinueWith(Action<Task>, TaskContinuationOptions)

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^> ^ continuationAction, System::Threading::Tasks::TaskContinuationOptions continuationOptions);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task> continuationAction, System.Threading.Tasks.TaskContinuationOptions continuationOptions);

member this.ContinueWith : Action<System.Threading.Tasks.Task> * System.Threading.Tasks.TaskContinuationOptions -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task), continuationOptions As TaskContinuationOptions) As Task

Parámetros

continuationAction: Action<Task>

Una acción para ejecutarse según el continuationOptions especificado.An action to run according to the specified continuationOptions. Cuando se ejecute, al delegado se le pasará la tarea completada como un argumento.When run, the delegate will be passed the completed task as an argument.

continuationOptions: TaskContinuationOptions

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

Ejemplos

En el ejemplo siguiente se muestra TaskContinuationOptions Cómo usar para especificar que una tarea de continuación debe ejecutarse sincrónicamente cuando se completa la tarea antecedente.The following example demonstrates using TaskContinuationOptions to specify that a continuation task should run synchronously when the antecedent task completes. (Si la tarea especificada ya se ha completado en el momento en que ContinueWith se llama a, la continuación sincrónica se ejecutará en el subproceso que llama a ContinueWith ).(If the specified task has already completed by the time ContinueWith is called, the synchronous continuation will run on the thread calling ContinueWith.)

public class TaskCounter  
{  
   private volatile int _count;  

   public void Track(Task t)  
   {  
      if (t == null) throw new ArgumentNullException("t");  
      Interlocked.Increment(ref _count);  
      t.ContinueWith(ct => Interlocked.Decrement(ref _count), TaskContinuationOptions.ExecuteSynchronously);  
   }  

   public int NumberOfActiveTasks { get { return _count; } }  
}

Public Class TaskCounter  
   Private _count as Integer  

   Public Sub Track(ByVal t as Task)  
      If t is Nothing Then Throw New ArgumentNullException("t")  
      Interlocked.Increment(_count)  
      t.ContinueWith(Sub(ct)  
                        Interlocked.Decrement(_count)  
                     End Sub,  
                     TaskContinuationOptions.ExecuteSynchronously)  
   End Sub  

   Public ReadOnly Property NumberOfActiveTasks As Integer  
      Get  
         Return _count  
      End Get  
   End Property  
End Class

Comentarios

El devuelto Task no se programará para su ejecución hasta que se complete la tarea actual.The returned Task will not be scheduled for execution until the current task has completed. Si no se cumplen los criterios de continuación especificados a través del continuationOptions parámetro, la tarea de continuación se cancelará en lugar de programada.If the continuation criteria specified through the continuationOptions parameter are not met, the continuation task will be canceled instead of scheduled.

Se aplica a

ContinueWith(Action<Task>, CancellationToken)

Crea una continuación que recibe un token de cancelación y se ejecuta de forma asincrónica cuando el elemento Task de destino se completa.Creates a continuation that receives a cancellation token and executes asynchronously when the target Task completes.

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^> ^ continuationAction, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task> continuationAction, System.Threading.CancellationToken cancellationToken);

member this.ContinueWith : Action<System.Threading.Tasks.Task> * System.Threading.CancellationToken -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task), cancellationToken As CancellationToken) As Task

Parámetros

continuationAction: Action<Task>

Acción que se va a ejecutar cuando se complete el objeto Task.An action to run when the Task completes. Cuando se ejecute, al delegado se le pasará la tarea completada como un argumento.When run, the delegate will be passed the completed task as an argument.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ObjectDisposedException

El CancellationTokenSource que creó el token ya se ha eliminado.The CancellationTokenSource that created the token has already been disposed.

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

Comentarios

Se aplica a

ContinueWith(Action<Task>)

Crea una continuación que se ejecuta de manera asincrónica cuando se completa el objeto Task de destino.Creates a continuation that executes asynchronously when the target Task completes.

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^> ^ continuationAction);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task> continuationAction);

member this.ContinueWith : Action<System.Threading.Tasks.Task> -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task)) As Task

Parámetros

continuationAction: Action<Task>

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

Ejemplos

En el ejemplo siguiente se define una tarea que rellena una matriz con valores de fecha y hora aleatorios 100.The following example defines a task that populates an array with 100 random date and time values. Utiliza el ContinueWith(Action<Task>) método para seleccionar los valores de fecha más antiguos y los más recientes una vez que la matriz se rellena por completo.It uses the ContinueWith(Action<Task>) method to select the earliest and the latest date values once the array is fully populated.

using System;
using System.Threading.Tasks;

public class Example
{
   public static void Main()
   {
      var firstTask = Task.Factory.StartNew( () => {
                               Random rnd = new Random();
                               DateTime[] dates = new DateTime[100];
                               Byte[] buffer = new Byte[8];
                               int ctr = dates.GetLowerBound(0);
                               while (ctr <= dates.GetUpperBound(0)) {
                                  rnd.NextBytes(buffer);
                                  long ticks = BitConverter.ToInt64(buffer, 0);
                                  if (ticks <= DateTime.MinValue.Ticks | ticks >= DateTime.MaxValue.Ticks)
                                     continue;

                                  dates[ctr] = new DateTime(ticks);
                                  ctr++;
                               }
                               return dates;
                            } ); 
                         
      Task continuationTask = firstTask.ContinueWith( (antecedent) => {
                             DateTime[] dates = antecedent.Result;
                             DateTime earliest = dates[0];
                             DateTime latest = earliest;
                             
                             for (int ctr = dates.GetLowerBound(0) + 1; ctr <= dates.GetUpperBound(0); ctr++) {
                                if (dates[ctr] < earliest) earliest = dates[ctr];
                                if (dates[ctr] > latest) latest = dates[ctr];
                             }
                             Console.WriteLine("Earliest date: {0}", earliest);
                             Console.WriteLine("Latest date: {0}", latest);
                          } );                      
      // Since a console application otherwise terminates, wait for the continuation to complete.
     continuationTask.Wait();
   }
}
// The example displays output like the following:
//       Earliest date: 2/11/0110 12:03:41 PM
//       Latest date: 7/29/9989 2:14:49 PM

Imports System.Threading.Tasks

Module Example
   Public Sub Main()
      Dim firstTask = Task.Factory.StartNew( Function()
                               Dim rnd As New Random()
                               Dim dates(99) As Date
                               Dim buffer(7) As Byte
                               Dim ctr As Integer = dates.GetLowerBound(0)
                               Do While ctr <= dates.GetUpperBound(0)
                                  rnd.NextBytes(buffer)
                                  Dim ticks As Long = BitConverter.ToInt64(buffer, 0)
                                  If ticks <= DateTime.MinValue.Ticks Or ticks >= DateTime.MaxValue.Ticks Then Continue Do

                                  dates(ctr) = New Date(ticks)
                                  ctr += 1
                               Loop
                               Return dates
                            End Function )
                         
      Dim continuationTask As Task = firstTask.ContinueWith( Sub(antecedent)
                             Dim dates() As Date = antecedent.Result
                             Dim earliest As Date = dates(0)
                             Dim latest As Date = earliest
                             
                             For ctr As Integer = dates.GetLowerBound(0) + 1 To dates.GetUpperBound(0)
                                If dates(ctr) < earliest Then earliest = dates(ctr)
                                If dates(ctr) > latest Then latest = dates(ctr)
                             Next
                             Console.WriteLine("Earliest date: {0}", earliest)
                             Console.WriteLine("Latest date: {0}", latest)
                          End Sub)                      
      ' Since a console application otherwise terminates, wait for the continuation to complete.
      continuationTask.Wait()
   End Sub
End Module
' The example displays output like the following:
'       Earliest date: 2/11/0110 12:03:41 PM
'       Latest date: 7/29/9989 2:14:49 PM

Dado que una aplicación de consola puede finalizar antes de que se ejecute la tarea de continuación, Wait() se llama al método para asegurarse de que la continuación finaliza su ejecución antes de que finalice el ejemplo.Because a console application may terminate before the continuation task executes, the Wait() method is called to ensure that the continuation finishes executing before the example ends.

Para ver un ejemplo adicional, consulte encadenar tareas mediante tareas de continuación.For an additional example, see Chaining Tasks by Using Continuation Tasks.

Comentarios

Se aplica a

ContinueWith(Action<Task>, TaskScheduler)

public:
 System::Threading::Tasks::Task ^ ContinueWith(Action<System::Threading::Tasks::Task ^> ^ continuationAction, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task ContinueWith (Action<System.Threading.Tasks.Task> continuationAction, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Action<System.Threading.Tasks.Task> * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task

Public Function ContinueWith (continuationAction As Action(Of Task), scheduler As TaskScheduler) As Task

Parámetros

continuationAction: Action<Task>

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task

Nuevo objeto Task de continuación.A new continuation Task.

Excepciones

ObjectDisposedException

Se ha eliminado Task.The Task has been disposed.

ArgumentNullException

El argumento continuationAction es null.The continuationAction argument is null.

O bien-or- El argumento scheduler es null.The scheduler argument is null.

Comentarios

Se aplica a

ContinueWith<TResult>(Func<Task,Object,TResult>, Object, TaskContinuationOptions)

Crea una continuación que se ejecuta según las opciones de continuación de la tarea especificadas cuando el elemento Task de destino se completa.Creates a continuation that executes based on the specified task continuation options when the target Task completes. La continuación recibe información de estado proporcionada por el autor de la llamada.The continuation receives caller-supplied state information.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, System::Object ^, TResult> ^ continuationFunction, System::Object ^ state, System::Threading::Tasks::TaskContinuationOptions continuationOptions);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object,TResult> continuationFunction, object state, System.Threading.Tasks.TaskContinuationOptions continuationOptions);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object?,TResult> continuationFunction, object? state, System.Threading.Tasks.TaskContinuationOptions continuationOptions);

member this.ContinueWith : Func<System.Threading.Tasks.Task, obj, 'Result> * obj * System.Threading.Tasks.TaskContinuationOptions -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, Object, TResult), state As Object, continuationOptions As TaskContinuationOptions) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,Object,TResult>

Función que se va a ejecutar cuando se complete el objeto Task.A function to run when the Task completes. Cuando se ejecute, se pasarán al delegado la tarea completada y el objeto de estado proporcionado por el llamador como argumentos.When run, the delegate will be passed the completed task and the caller-supplied state object as arguments.

state: Object

Objeto que representa los datos que la función de continuación va a usar.An object representing data to be used by the continuation function.

continuationOptions: TaskContinuationOptions

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

Comentarios

El devuelto Task<TResult> no se programará para su ejecución hasta que se complete la tarea actual.The returned Task<TResult> will not be scheduled for execution until the current task has completed. Si no se cumplen los criterios de continuación especificados a través del continuationOptions parámetro, la tarea de continuación se cancelará en lugar de programada.If the continuation criteria specified through the continuationOptions parameter are not met, the continuation task will be canceled instead of scheduled.

Se aplica a

ContinueWith<TResult>(Func<Task,Object,TResult>, Object, CancellationToken, TaskContinuationOptions, TaskScheduler)

Crea una continuación que se ejecuta según las opciones de continuación de la tarea especificadas cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes based on the specified task continuation options when the target Task completes and returns a value. La continuación recibe información de estado proporcionada por el autor de la llamada y un token de cancelación y usa el programador especificado.The continuation receives caller-supplied state information and a cancellation token and uses the specified scheduler.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, System::Object ^, TResult> ^ continuationFunction, System::Object ^ state, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskContinuationOptions continuationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object,TResult> continuationFunction, object state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskContinuationOptions continuationOptions, System.Threading.Tasks.TaskScheduler scheduler);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object?,TResult> continuationFunction, object? state, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskContinuationOptions continuationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Func<System.Threading.Tasks.Task, obj, 'Result> * obj * System.Threading.CancellationToken * System.Threading.Tasks.TaskContinuationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, Object, TResult), state As Object, cancellationToken As CancellationToken, continuationOptions As TaskContinuationOptions, scheduler As TaskScheduler) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,Object,TResult>

state: Object

Objeto que representa los datos que la función de continuación va a usar.An object representing data to be used by the continuation function.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

continuationOptions: TaskContinuationOptions

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ArgumentNullException

El argumento scheduler es null.The scheduler argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

ObjectDisposedException

Ya se eliminó el CancellationToken proporcionado.The provided CancellationToken has already been disposed.

Comentarios

El devuelto Task<TResult> no se programará para su ejecución hasta que se complete la tarea actual.The returned Task<TResult> will not be scheduled for execution until the current task has completed. Si no se cumplen los criterios especificados a través del continuationOptions parámetro, la tarea de continuación se cancelará en lugar de programar.If the criteria specified through the continuationOptions parameter are not met, the continuation task will be canceled instead of scheduled.

Se aplica a

ContinueWith<TResult>(Func<Task,TResult>, CancellationToken, TaskContinuationOptions, TaskScheduler)

Crea una continuación que se ejecuta según las opciones de continuación especificadas y devuelve un valor.Creates a continuation that executes according to the specified continuation options and returns a value. Se pasa un token de cancelación a la continuación y usa un programador especificado.The continuation is passed a cancellation token and uses a specified scheduler.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, TResult> ^ continuationFunction, System::Threading::CancellationToken cancellationToken, System::Threading::Tasks::TaskContinuationOptions continuationOptions, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,TResult> continuationFunction, System.Threading.CancellationToken cancellationToken, System.Threading.Tasks.TaskContinuationOptions continuationOptions, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Func<System.Threading.Tasks.Task, 'Result> * System.Threading.CancellationToken * System.Threading.Tasks.TaskContinuationOptions * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, TResult), cancellationToken As CancellationToken, continuationOptions As TaskContinuationOptions, scheduler As TaskScheduler) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,TResult>

Una función que se ejecutará según el parámetro continuationOptions especificado.A function to run according to the specified continuationOptions. Cuando se ejecute, al delegado se le pasará la tarea completada como un argumento.When run, the delegate will be passed the completed task as an argument.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

continuationOptions: TaskContinuationOptions

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ObjectDisposedException

Se ha eliminado Task.The Task has been disposed.

O bien-or- El CancellationTokenSource que creó el token ya se ha eliminado.The CancellationTokenSource that created the token has already been disposed.

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

O bien-or- El argumento scheduler es null.The scheduler argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

Ejemplos

En el ejemplo siguiente se muestra cómo usar el método ContinueWith con opciones de continuación:The following example shows how to use the ContinueWith method with continuation options:

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

class ContinuationOptionsDemo
{
    // Demonstrated features:
    //      TaskContinuationOptions
    //		Task.ContinueWith()
    // 		Task.Factory
    //		Task.Wait()
    // Expected results:
    // 		This sample demonstrates branched continuation sequences - Task+Commit or Task+Rollback.
    //      Notice that no if statements are used.
    //		The first sequence is successful - tran1 and commitTran1 are executed. rollbackTran1 is canceled.
    //		The second sequence is unsuccessful - tran2 and rollbackTran2 are executed. tran2 is faulted, and commitTran2 is canceled.
    // Documentation:
    //		http://msdn.microsoft.com/library/system.threading.tasks.taskcontinuationoptions(VS.100).aspx
    static void Main()
    {
        Action success = () => Console.WriteLine("Task={0}, Thread={1}: Begin successful transaction",
                                                Task.CurrentId, Thread.CurrentThread.ManagedThreadId);
        Action failure = () =>
        {
            Console.WriteLine("Task={0}, Thread={1}: Begin transaction and encounter an error",
                                Task.CurrentId, Thread.CurrentThread.ManagedThreadId);
            throw new InvalidOperationException("SIMULATED EXCEPTION");
        };

        Action<Task> commit = (antecendent) => Console.WriteLine("Task={0}, Thread={1}: Commit transaction",
                                                                Task.CurrentId, Thread.CurrentThread.ManagedThreadId);
        Action<Task> rollback = (antecendent) =>
        {
            // "Observe" your antecedent's exception so as to avoid an exception
            // being thrown on the finalizer thread
            var unused = antecendent.Exception;

            Console.WriteLine("Task={0}, Thread={1}: Rollback transaction",
                  Task.CurrentId, Thread.CurrentThread.ManagedThreadId);
        };

        // Successful transaction - Begin + Commit
        Console.WriteLine("Demonstrating a successful transaction");

        // Initial task
        // Treated as "fire-and-forget" -- any exceptions will be cleaned up in rollback continuation
        Task tran1 = Task.Factory.StartNew(success);

        // The following task gets scheduled only if tran1 completes successfully
        var commitTran1 = tran1.ContinueWith(commit, TaskContinuationOptions.OnlyOnRanToCompletion);

        // The following task gets scheduled only if tran1 DOES NOT complete successfully
        var rollbackTran1 = tran1.ContinueWith(rollback, TaskContinuationOptions.NotOnRanToCompletion);

        // For demo purposes, wait for the sample to complete
        commitTran1.Wait();

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

        // Failed transaction - Begin + exception + Rollback
        Console.WriteLine("\nDemonstrating a failed transaction");

        // Initial task
        // Treated as "fire-and-forget" -- any exceptions will be cleaned up in rollback continuation
        Task tran2 = Task.Factory.StartNew(failure);

        // The following task gets scheduled only if tran2 completes successfully
        var commitTran2 = tran2.ContinueWith(commit, TaskContinuationOptions.OnlyOnRanToCompletion);

        // The following task gets scheduled only if tran2 DOES NOT complete successfully
        var rollbackTran2 = tran2.ContinueWith(rollback, TaskContinuationOptions.NotOnRanToCompletion);

        // For demo purposes, wait for the sample to complete
        rollbackTran2.Wait();
    }
}

Imports System.Threading
Imports System.Threading.Tasks

Module ContuationOptionsDemo
    ' Demonstrated features:
    '   TaskContinuationOptions
    '   Task.ContinueWith()
    '   Task.Factory
    '   Task.Wait()
    ' Expected results:
    '   This sample demonstrates branched continuation sequences - Task+Commit or Task+Rollback.
    '   Notice that no if statements are used.
    '   The first sequence is successful - tran1 and commitTran1 are executed. rollbackTran1 is canceled.
    '   The second sequence is unsuccessful - tran2 and rollbackTran2 are executed. tran2 is faulted, and commitTran2 is canceled.
    ' Documentation:
    '   http://msdn.microsoft.com/library/system.threading.tasks.taskcontinuationoptions(VS.100).aspx
    Private Sub Main()
        Dim success As Action = Sub()
                                    Console.WriteLine("Task={0}, Thread={1}: Begin successful transaction", Task.CurrentId, Thread.CurrentThread.ManagedThreadId)
                                End Sub

        Dim failure As Action = Sub()
                                    Console.WriteLine("Task={0}, Thread={1}: Begin transaction and encounter an error", Task.CurrentId, Thread.CurrentThread.ManagedThreadId)
                                    Throw New InvalidOperationException("SIMULATED EXCEPTION")
                                End Sub

        Dim commit As Action(Of Task) = Sub(antecendent)
                                            Console.WriteLine("Task={0}, Thread={1}: Commit transaction", Task.CurrentId, Thread.CurrentThread.ManagedThreadId)
                                        End Sub

        Dim rollback As Action(Of Task) = Sub(antecendent)
                                              ' "Observe" your antecedent's exception so as to avoid an exception
                                              ' being thrown on the finalizer thread
                                              Dim unused = antecendent.Exception

                                              Console.WriteLine("Task={0}, Thread={1}: Rollback transaction", Task.CurrentId, Thread.CurrentThread.ManagedThreadId)
                                          End Sub

        ' Successful transaction - Begin + Commit
        Console.WriteLine("Demonstrating a successful transaction")

        ' Initial task
        ' Treated as "fire-and-forget" -- any exceptions will be cleaned up in rollback continuation
        Dim tran1 As Task = Task.Factory.StartNew(success)

        ' The following task gets scheduled only if tran1 completes successfully
        Dim commitTran1 = tran1.ContinueWith(commit, TaskContinuationOptions.OnlyOnRanToCompletion)

        ' The following task gets scheduled only if tran1 DOES NOT complete successfully
        Dim rollbackTran1 = tran1.ContinueWith(rollback, TaskContinuationOptions.NotOnRanToCompletion)

        ' For demo purposes, wait for the sample to complete
        commitTran1.Wait()

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


        ' Failed transaction - Begin + exception + Rollback 
        Console.WriteLine(vbLf & "Demonstrating a failed transaction")

        ' Initial task
        ' Treated as "fire-and-forget" -- any exceptions will be cleaned up in rollback continuation
        Dim tran2 As Task = Task.Factory.StartNew(failure)

        ' The following task gets scheduled only if tran2 completes successfully
        Dim commitTran2 = tran2.ContinueWith(commit, TaskContinuationOptions.OnlyOnRanToCompletion)

        ' The following task gets scheduled only if tran2 DOES NOT complete successfully
        Dim rollbackTran2 = tran2.ContinueWith(rollback, TaskContinuationOptions.NotOnRanToCompletion)

        ' For demo purposes, wait for the sample to complete
        rollbackTran2.Wait()
    End Sub
End Module

Comentarios

El devuelto Task<TResult> no se programará para su ejecución hasta que se complete la tarea actual.The returned Task<TResult> will not be scheduled for execution until the current task has completed. Si no se cumplen los criterios especificados a través del continuationOptions parámetro, la tarea de continuación se cancelará en lugar de programar.If the criteria specified through the continuationOptions parameter are not met, the continuation task will be canceled instead of scheduled.

Se aplica a

ContinueWith<TResult>(Func<Task,Object,TResult>, Object, TaskScheduler)

Crea una continuación que se ejecuta de manera asincrónica cuando se completa el objeto Task de destino.Creates a continuation that executes asynchronously when the target Task completes. La continuación recibe información de estado proporcionada por el autor de la llamada y usa a un programador especificado.The continuation receives caller-supplied state information and uses a specified scheduler.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, System::Object ^, TResult> ^ continuationFunction, System::Object ^ state, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object,TResult> continuationFunction, object state, System.Threading.Tasks.TaskScheduler scheduler);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object?,TResult> continuationFunction, object? state, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Func<System.Threading.Tasks.Task, obj, 'Result> * obj * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, Object, TResult), state As Object, scheduler As TaskScheduler) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,Object,TResult>

state: Object

Objeto que representa los datos que la función de continuación va a usar.An object representing data to be used by the continuation function.

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ArgumentNullException

El argumento scheduler es null.The scheduler argument is null.

Comentarios

El devuelto Task<TResult> no se programará para su ejecución hasta que se complete la tarea actual, si se completa debido a que la ejecución se ha completado correctamente, a que se ha producido un error debido a una excepción no controlada o a un cierre temprano debido a su cancelación.The returned Task<TResult> will not be scheduled for execution until the current task has completed, whether it completes due to running to completion successfully, faulting due to an unhandled exception, or exiting out early due to being canceled.

Se aplica a

ContinueWith<TResult>(Func<Task,Object,TResult>, Object, CancellationToken)

Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task completes and returns a value. La continuación recibe información de estado proporcionada por el autor de la llamada y un token de cancelación.The continuation receives caller-supplied state information and a cancellation token.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, System::Object ^, TResult> ^ continuationFunction, System::Object ^ state, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object,TResult> continuationFunction, object state, System.Threading.CancellationToken cancellationToken);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object?,TResult> continuationFunction, object? state, System.Threading.CancellationToken cancellationToken);

member this.ContinueWith : Func<System.Threading.Tasks.Task, obj, 'Result> * obj * System.Threading.CancellationToken -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, Object, TResult), state As Object, cancellationToken As CancellationToken) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,Object,TResult>

state: Object

Objeto que representa los datos que la función de continuación va a usar.An object representing data to be used by the continuation function.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

ObjectDisposedException

Ya se eliminó el CancellationToken proporcionado.The provided CancellationToken has already been disposed.

Comentarios

Se aplica a

ContinueWith<TResult>(Func<Task,Object,TResult>, Object)

Crea una continuación que recibe información de estado proporcionada por el autor de la llamada y se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that receives caller-supplied state information and executes asynchronously when the target Task completes and returns a value.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, System::Object ^, TResult> ^ continuationFunction, System::Object ^ state);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object,TResult> continuationFunction, object state);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,object?,TResult> continuationFunction, object? state);

member this.ContinueWith : Func<System.Threading.Tasks.Task, obj, 'Result> * obj -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, Object, TResult), state As Object) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,Object,TResult>

state: Object

Objeto que representa los datos que la función de continuación va a usar.An object representing data to be used by the continuation function.

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

Comentarios

Se aplica a

ContinueWith<TResult>(Func<Task,TResult>, TaskContinuationOptions)

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, TResult> ^ continuationFunction, System::Threading::Tasks::TaskContinuationOptions continuationOptions);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,TResult> continuationFunction, System.Threading.Tasks.TaskContinuationOptions continuationOptions);

member this.ContinueWith : Func<System.Threading.Tasks.Task, 'Result> * System.Threading.Tasks.TaskContinuationOptions -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, TResult), continuationOptions As TaskContinuationOptions) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,TResult>

Una función para ejecutar según la condición especificada en continuationOptions.A function to run according to the condition specified in continuationOptions. Cuando se ejecute, al delegado se le pasará la tarea completada como un argumento.When run, the delegate will be passed the completed task as an argument.

continuationOptions: TaskContinuationOptions

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ObjectDisposedException

Se ha eliminado Task.The Task has been disposed.

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

ArgumentOutOfRangeException

El argumento continuationOptions especifica un valor no válido para TaskContinuationOptions.The continuationOptions argument specifies an invalid value for TaskContinuationOptions.

Comentarios

Se aplica a

ContinueWith<TResult>(Func<Task,TResult>, CancellationToken)

Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task completes and returns a value. La continuación recibe un token de cancelación.The continuation receives a cancellation token.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, TResult> ^ continuationFunction, System::Threading::CancellationToken cancellationToken);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,TResult> continuationFunction, System.Threading.CancellationToken cancellationToken);

member this.ContinueWith : Func<System.Threading.Tasks.Task, 'Result> * System.Threading.CancellationToken -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, TResult), cancellationToken As CancellationToken) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,TResult>

Función que se va a ejecutar cuando se complete el objeto Task.A function to run when the Task completes. Cuando se ejecute, al delegado se le pasará la tarea completada como un argumento.When run, the delegate will be passed the completed task as an argument.

cancellationToken: CancellationToken

El CancellationToken que se asignará a la nueva tarea de continuación.The CancellationToken that will be assigned to the new continuation task.

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ObjectDisposedException

Se ha eliminado Task.The Task has been disposed.

O bien-or- El CancellationTokenSource que creó el token ya se ha eliminado.The CancellationTokenSource that created the token has already been disposed.

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

Comentarios

Se aplica a

ContinueWith<TResult>(Func<Task,TResult>, TaskScheduler)

Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task completes and returns a value. La continuación usa un programador especificado.The continuation uses a specified scheduler.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, TResult> ^ continuationFunction, System::Threading::Tasks::TaskScheduler ^ scheduler);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,TResult> continuationFunction, System.Threading.Tasks.TaskScheduler scheduler);

member this.ContinueWith : Func<System.Threading.Tasks.Task, 'Result> * System.Threading.Tasks.TaskScheduler -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, TResult), scheduler As TaskScheduler) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,TResult>

scheduler: TaskScheduler

Objeto TaskScheduler que se va a asociar a la tarea de continuación y se va a usar para su ejecución.The TaskScheduler to associate with the continuation task and to use for its execution.

Devoluciones

Task<TResult>

Nuevo objeto Task<TResult> de continuación.A new continuation Task<TResult>.

Excepciones

ObjectDisposedException

Se ha eliminado Task.The Task has been disposed.

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

O bien-or- El argumento scheduler es null.The scheduler argument is null.

Comentarios

Se aplica a

ContinueWith<TResult>(Func<Task,TResult>)

Crea una continuación que se ejecuta de forma asincrónica cuando el elemento Task<TResult> de destino se completa y devuelve un valor.Creates a continuation that executes asynchronously when the target Task<TResult> completes and returns a value.

public:
generic <typename TResult>
 System::Threading::Tasks::Task<TResult> ^ ContinueWith(Func<System::Threading::Tasks::Task ^, TResult> ^ continuationFunction);

public System.Threading.Tasks.Task<TResult> ContinueWith<TResult> (Func<System.Threading.Tasks.Task,TResult> continuationFunction);

member this.ContinueWith : Func<System.Threading.Tasks.Task, 'Result> -> System.Threading.Tasks.Task<'Result>

Public Function ContinueWith(Of TResult) (continuationFunction As Func(Of Task, TResult)) As Task(Of TResult)

Parámetros de tipo

TResult

Tipo de resultado generado por la continuación.The type of the result produced by the continuation.

Parámetros

continuationFunction: Func<Task,TResult>

Función que se va a ejecutar cuando se complete el objeto Task<TResult>.A function to run when the Task<TResult> completes. Cuando se ejecute, al delegado se le pasará la tarea completada como un argumento.When run, the delegate will be passed the completed task as an argument.

Devoluciones

Task<TResult>

Una tarea de continuación nueva.A new continuation task.

Excepciones

ObjectDisposedException

Se ha eliminado Task.The Task has been disposed.

ArgumentNullException

El argumento continuationFunction es null.The continuationFunction argument is null.

Ejemplos

En el ejemplo siguiente se muestra cómo usar el método ContinueWith:The following example shows how to use the ContinueWith method:

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

class ContinuationSimpleDemo
{
    // Demonstrated features:
    // 		Task.Factory
    //		Task.ContinueWith()
    //		Task.Wait()
    // Expected results:
    // 		A sequence of three unrelated tasks is created and executed in this order - alpha, beta, gamma.
    //		A sequence of three related tasks is created - each task negates its argument and passes is to the next task: 5, -5, 5 is printed.
    //		A sequence of three unrelated tasks is created where tasks have different types.
    // Documentation:
    //		http://msdn.microsoft.com/library/system.threading.tasks.taskfactory_members(VS.100).aspx
    static void Main()
    {
        Action<string> action =
            (str) =>
                Console.WriteLine("Task={0}, str={1}, Thread={2}", Task.CurrentId, str, Thread.CurrentThread.ManagedThreadId);

        // Creating a sequence of action tasks (that return no result).
        Console.WriteLine("Creating a sequence of action tasks (that return no result)");
        Task.Factory.StartNew(() => action("alpha"))
            .ContinueWith(antecendent => action("beta"))        // Antecedent data is ignored
            .ContinueWith(antecendent => action("gamma"))
            .Wait();

        Func<int, int> negate =
            (n) =>
            {
                Console.WriteLine("Task={0}, n={1}, -n={2}, Thread={3}", Task.CurrentId, n, -n, Thread.CurrentThread.ManagedThreadId);
                return -n;
            };

        // Creating a sequence of function tasks where each continuation uses the result from its antecendent
        Console.WriteLine("\nCreating a sequence of function tasks where each continuation uses the result from its antecendent");
        Task<int>.Factory.StartNew(() => negate(5))
            .ContinueWith(antecendent => negate(antecendent.Result))		// Antecedent result feeds into continuation
            .ContinueWith(antecendent => negate(antecendent.Result))
            .Wait();

        // Creating a sequence of tasks where you can mix and match the types
        Console.WriteLine("\nCreating a sequence of tasks where you can mix and match the types");
        Task<int>.Factory.StartNew(() => negate(6))
            .ContinueWith(antecendent => action("x"))
            .ContinueWith(antecendent => negate(7))
            .Wait();
    }
}

Imports System.Threading
Imports System.Threading.Tasks

Module ContinuationDemo

    ' Demonstrated features:
    '   Task.Factory
    '   Task.ContinueWith()
    '   Task.Wait()
    ' Expected results:
    '   A sequence of three unrelated tasks is created and executed in this order - alpha, beta, gamma.
    '   A sequence of three related tasks is created - each task negates its argument and passes is to the next task: 5, -5, 5 is printed.
    '   A sequence of three unrelated tasks is created where tasks have different types.
    ' Documentation:
    '   http://msdn.microsoft.com/library/system.threading.tasks.taskfactory_members(VS.100).aspx
    Sub Main()
        Dim action As Action(Of String) = Sub(str) Console.WriteLine("Task={0}, str={1}, Thread={2}", Task.CurrentId, str, Thread.CurrentThread.ManagedThreadId)

        ' Creating a sequence of action tasks (that return no result).
        Console.WriteLine("Creating a sequence of action tasks (that return no result)")
        ' Continuations ignore antecedent data
        Task.Factory.StartNew(Sub() action("alpha")).ContinueWith(Sub(antecendent) action("beta")).ContinueWith(Sub(antecendent) action("gamma")).Wait()


        Dim negate As Func(Of Integer, Integer) = Function(n)
                                                      Console.WriteLine("Task={0}, n={1}, -n={2}, Thread={3}", Task.CurrentId, n, -n, Thread.CurrentThread.ManagedThreadId)
                                                      Return -n
                                                  End Function

        ' Creating a sequence of function tasks where each continuation uses the result from its antecendent
        Console.WriteLine(vbLf & "Creating a sequence of function tasks where each continuation uses the result from its antecendent")
        Task(Of Integer).Factory.StartNew(Function() negate(5)).ContinueWith(Function(antecendent) negate(antecendent.Result)).ContinueWith(Function(antecendent) negate(antecendent.Result)).Wait()


        ' Creating a sequence of tasks where you can mix and match the types
        Console.WriteLine(vbLf & "Creating a sequence of tasks where you can mix and match the types")
        Task(Of Integer).Factory.StartNew(Function() negate(6)).ContinueWith(Sub(antecendent) action("x")).ContinueWith(Function(antecendent) negate(7)).Wait()
    End Sub
End Module

Comentarios

Se aplica a