RegisteredWaitHandle RegisteredWaitHandle RegisteredWaitHandle RegisteredWaitHandle Class

Definición

Representa un identificador que se registró al llamar a RegisterWaitForSingleObject(WaitHandle, WaitOrTimerCallback, Object, UInt32, Boolean).Represents a handle that has been registered when calling RegisterWaitForSingleObject(WaitHandle, WaitOrTimerCallback, Object, UInt32, Boolean). Esta clase no puede heredarse.This class cannot be inherited.

public ref class RegisteredWaitHandle sealed : MarshalByRefObject
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class RegisteredWaitHandle : MarshalByRefObject
type RegisteredWaitHandle = class
    inherit MarshalByRefObject
Public NotInheritable Class RegisteredWaitHandle
Inherits MarshalByRefObject
Herencia
RegisteredWaitHandleRegisteredWaitHandleRegisteredWaitHandleRegisteredWaitHandle
Atributos

Ejemplos

En el ejemplo siguiente se muestra cómo utilizar RegisteredWaitHandle para determinar por qué se llama a un método de devolución de llamada y cómo anular el registro de una tarea si la devolución de llamada se produjo porque se señaló el identificador de espera.The following example shows how to use a RegisteredWaitHandle to determine why a callback method is called, and how to unregister a task if the callback occurred because the wait handle was signaled.

En el ejemplo también se muestra cómo usar RegisterWaitForSingleObject el método para ejecutar un método de devolución de llamada especificado cuando se señala un identificador de espera especificado.The example also shows how to use the RegisterWaitForSingleObject method to execute a specified callback method when a specified wait handle is signaled. En este ejemplo, el método de devolución WaitProcde llamada es y el identificador de AutoResetEventespera es.In this example, the callback method is WaitProc, and the wait handle is an AutoResetEvent.

En el ejemplo se TaskInfo define una clase que contiene la información que se pasa a la devolución de llamada cuando se ejecuta.The example defines a TaskInfo class to hold the information that is passed to the callback when it executes. En el ejemplo se TaskInfo crea un objeto y se le asignan algunos datos de cadena.The example creates a TaskInfo object and assigns it some string data. El RegisteredWaitHandle devuelto por el RegisterWaitForSingleObject Handle método se asigna TaskInfo al campo del objeto para que el método de devolución de llamada tenga acceso a RegisteredWaitHandle.The RegisteredWaitHandle that is returned by the RegisterWaitForSingleObject method is assigned to the Handle field of the TaskInfo object so that the callback method has access to the RegisteredWaitHandle.

Además de TaskInfo especificar como el objeto que se va a pasar al método de devolución de llamada, la RegisterWaitForSingleObject llamada al método AutoResetEvent especifica el que la tarea esperará, WaitOrTimerCallback un delegado que representa WaitProc el método de devolución de llamada, un un segundo intervalo de tiempo de espera y varias devoluciones de llamada.In addition to specifying TaskInfo as the object to pass to the callback method, the call to the RegisterWaitForSingleObject method specifies the AutoResetEvent that the task will wait for, a WaitOrTimerCallback delegate that represents the WaitProc callback method, a one second time-out interval, and multiple callbacks.

Cuando el subproceso principal señala AutoResetEvent a llamando a Set su método, WaitOrTimerCallback se invoca al delegado.When the main thread signals the AutoResetEvent by calling its Set method, the WaitOrTimerCallback delegate is invoked. El WaitProc método prueba RegisteredWaitHandle para determinar si se ha producido un tiempo de espera.The WaitProc method tests RegisteredWaitHandle to determine whether a time-out occurred. Si se invocó la devolución de llamada porque se señaló el identificador de espera WaitProc , el método anula el RegisteredWaitHandleregistro de y detiene las devoluciones de llamada adicionales.If the callback was invoked because the wait handle was signaled, the WaitProc method unregisters the RegisteredWaitHandle, stopping additional callbacks. En el caso de un tiempo de espera, la tarea continúa esperando.In the case of a time-out, the task continues to wait. El WaitProc método finaliza mediante la impresión de un mensaje en la consola.The WaitProc method ends by printing a message to the console.

using namespace System;
using namespace System::Threading;

// TaskInfo contains data that will be passed to the callback
// method.
public ref class TaskInfo
{
public:
   TaskInfo()
   {
      Handle = nullptr;
      OtherInfo = "default";
   }

   RegisteredWaitHandle^ Handle;
   String^ OtherInfo;
};

ref class Example
{
public:

   // The callback method executes when the registered wait times out,
   // or when the WaitHandle (in this case AutoResetEvent) is signaled.
   // WaitProc unregisters the WaitHandle the first time the event is 
   // signaled.
   static void WaitProc( Object^ state, bool timedOut )
   {
      
      // The state Object must be cast to the correct type, because the
      // signature of the WaitOrTimerCallback delegate specifies type
      // Object.
      TaskInfo^ ti = static_cast<TaskInfo^>(state);
      String^ cause = "TIMED OUT";
      if (  !timedOut )
      {
         cause = "SIGNALED";
         
         // If the callback method executes because the WaitHandle is
         // signaled, stop future execution of the callback method
         // by unregistering the WaitHandle.
         if ( ti->Handle != nullptr )
                  ti->Handle->Unregister( nullptr );
      }

      Console::WriteLine( "WaitProc( {0}) executes on thread {1}; cause = {2}.", ti->OtherInfo, Thread::CurrentThread->GetHashCode(), cause );
   }

};

int main()
{
   
   // The main thread uses AutoResetEvent to signal the
   // registered wait handle, which executes the callback
   // method.
   AutoResetEvent^ ev = gcnew AutoResetEvent( false );
   TaskInfo^ ti = gcnew TaskInfo;
   ti->OtherInfo = "First task";
   
   // The TaskInfo for the task includes the registered wait
   // handle returned by RegisterWaitForSingleObject.  This
   // allows the wait to be terminated when the object has
   // been signaled once (see WaitProc).
   ti->Handle = ThreadPool::RegisterWaitForSingleObject( ev, gcnew WaitOrTimerCallback( Example::WaitProc ), ti, 1000, false );
   
   // The main thread waits three seconds, to demonstrate the
   // time-outs on the queued thread, and then signals.
   Thread::Sleep( 3100 );
   Console::WriteLine( "Main thread signals." );
   ev->Set();
   
   // The main thread sleeps, which should give the callback
   // method time to execute.  If you comment out this line, the
   // program usually ends before the ThreadPool thread can execute.
   Thread::Sleep( 1000 );
   
   // If you start a thread yourself, you can wait for it to end
   // by calling Thread::Join.  This option is not available with 
   // thread pool threads.
   return 0;
}

using System;
using System.Threading;

// TaskInfo contains data that will be passed to the callback
// method.
public class TaskInfo {
    public RegisteredWaitHandle Handle = null;
    public string OtherInfo = "default";
}

public class Example {
    public static void Main(string[] args) {
        // The main thread uses AutoResetEvent to signal the
        // registered wait handle, which executes the callback
        // method.
        AutoResetEvent ev = new AutoResetEvent(false);

        TaskInfo ti = new TaskInfo();
        ti.OtherInfo = "First task";
        // The TaskInfo for the task includes the registered wait
        // handle returned by RegisterWaitForSingleObject.  This
        // allows the wait to be terminated when the object has
        // been signaled once (see WaitProc).
        ti.Handle = ThreadPool.RegisterWaitForSingleObject(
            ev,
            new WaitOrTimerCallback(WaitProc),
            ti,
            1000,
            false
        );

        // The main thread waits three seconds, to demonstrate the
        // time-outs on the queued thread, and then signals.
        Thread.Sleep(3100);
        Console.WriteLine("Main thread signals.");
        ev.Set();

        // The main thread sleeps, which should give the callback
        // method time to execute.  If you comment out this line, the
        // program usually ends before the ThreadPool thread can execute.
        Thread.Sleep(1000);
        // If you start a thread yourself, you can wait for it to end
        // by calling Thread.Join.  This option is not available with 
        // thread pool threads.
    }
   
    // The callback method executes when the registered wait times out,
    // or when the WaitHandle (in this case AutoResetEvent) is signaled.
    // WaitProc unregisters the WaitHandle the first time the event is 
    // signaled.
    public static void WaitProc(object state, bool timedOut) {
        // The state object must be cast to the correct type, because the
        // signature of the WaitOrTimerCallback delegate specifies type
        // Object.
        TaskInfo ti = (TaskInfo) state;

        string cause = "TIMED OUT";
        if (!timedOut) {
            cause = "SIGNALED";
            // If the callback method executes because the WaitHandle is
            // signaled, stop future execution of the callback method
            // by unregistering the WaitHandle.
            if (ti.Handle != null)
                ti.Handle.Unregister(null);
        } 

        Console.WriteLine("WaitProc( {0} ) executes on thread {1}; cause = {2}.",
            ti.OtherInfo, 
            Thread.CurrentThread.GetHashCode().ToString(), 
            cause
        );
    }
}
Imports System.Threading

' TaskInfo contains data that will be passed to the callback
' method.
Public Class TaskInfo
    public Handle As RegisteredWaitHandle = Nothing
    public OtherInfo As String = "default"
End Class

Public Class Example

    <MTAThread> _
    Public Shared Sub Main()
        ' The main thread uses AutoResetEvent to signal the
        ' registered wait handle, which executes the callback
        ' method.
        Dim ev As New AutoResetEvent(false)

        Dim ti As New TaskInfo()
        ti.OtherInfo = "First task"
        ' The TaskInfo for the task includes the registered wait
        ' handle returned by RegisterWaitForSingleObject.  This
        ' allows the wait to be terminated when the object has
        ' been signaled once (see WaitProc).
        ti.Handle = ThreadPool.RegisterWaitForSingleObject( _
            ev, _
            New WaitOrTimerCallback(AddressOf WaitProc), _
            ti, _
            1000, _
            false _
        )

        ' The main thread waits about three seconds, to demonstrate 
        ' the time-outs on the queued task, and then signals.
        Thread.Sleep(3100)
        Console.WriteLine("Main thread signals.")
        ev.Set()

        ' The main thread sleeps, which should give the callback
        ' method time to execute.  If you comment out this line, the
        ' program usually ends before the ThreadPool thread can execute.
        Thread.Sleep(1000)
        ' If you start a thread yourself, you can wait for it to end
        ' by calling Thread.Join.  This option is not available with 
        ' thread pool threads.
    End Sub
   
    ' The callback method executes when the registered wait times out,
    ' or when the WaitHandle (in this case AutoResetEvent) is signaled.
    ' WaitProc unregisters the WaitHandle the first time the event is 
    ' signaled.
    Public Shared Sub WaitProc(state As Object, timedOut As Boolean)
        ' The state object must be cast to the correct type, because the
        ' signature of the WaitOrTimerCallback delegate specifies type
        ' Object.
        Dim ti As TaskInfo = CType(state, TaskInfo)

        Dim cause As String = "TIMED OUT"
        If Not timedOut Then
            cause = "SIGNALED"
            ' If the callback method executes because the WaitHandle is
            ' signaled, stop future execution of the callback method
            ' by unregistering the WaitHandle.
            If Not ti.Handle Is Nothing Then
                ti.Handle.Unregister(Nothing)
            End If
        End If 

        Console.WriteLine("WaitProc( {0} ) executes on thread {1}; cause = {2}.", _
            ti.OtherInfo, _
            Thread.CurrentThread.GetHashCode().ToString(), _
            cause _
        )
    End Sub
End Class

Métodos

CreateObjRef(Type) CreateObjRef(Type) CreateObjRef(Type) CreateObjRef(Type)

Crea un objeto que contiene toda la información relevante necesaria para generar un proxy utilizado para comunicarse con un objeto remoto.Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.

(Inherited from MarshalByRefObject)
Equals(Object) Equals(Object) Equals(Object) Equals(Object)

Determina si el objeto especificado es igual al objeto actual.Determines whether the specified object is equal to the current object.

(Inherited from Object)
Finalize() Finalize() Finalize() Finalize()

Permite que un objeto intente liberar recursos y realizar otras operaciones de limpieza antes de que sea reclamado por la recolección de elementos no utilizados.Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.

GetHashCode() GetHashCode() GetHashCode() GetHashCode()

Sirve como la función hash predeterminada.Serves as the default hash function.

(Inherited from Object)
GetLifetimeService() GetLifetimeService() GetLifetimeService() GetLifetimeService()

Recupera el objeto de servicio de duración actual que controla la directiva de duración de esta instancia.Retrieves the current lifetime service object that controls the lifetime policy for this instance.

(Inherited from MarshalByRefObject)
GetType() GetType() GetType() GetType()

Obtiene el Type de la instancia actual.Gets the Type of the current instance.

(Inherited from Object)
InitializeLifetimeService() InitializeLifetimeService() InitializeLifetimeService() InitializeLifetimeService()

Obtiene un objeto de servicio de duración para controlar la directiva de duración de esta instancia.Obtains a lifetime service object to control the lifetime policy for this instance.

(Inherited from MarshalByRefObject)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

Crea una copia superficial del objeto Object actual.Creates a shallow copy of the current Object.

(Inherited from Object)
MemberwiseClone(Boolean) MemberwiseClone(Boolean) MemberwiseClone(Boolean) MemberwiseClone(Boolean)

Crea una copia superficial del objeto MarshalByRefObject actual.Creates a shallow copy of the current MarshalByRefObject object.

(Inherited from MarshalByRefObject)
ToString() ToString() ToString() ToString()

Devuelve una cadena que representa el objeto actual.Returns a string that represents the current object.

(Inherited from Object)
Unregister(WaitHandle) Unregister(WaitHandle) Unregister(WaitHandle) Unregister(WaitHandle)

Cancela una operación de espera registrada y emitida por el método RegisterWaitForSingleObject(WaitHandle, WaitOrTimerCallback, Object, UInt32, Boolean).Cancels a registered wait operation issued by the RegisterWaitForSingleObject(WaitHandle, WaitOrTimerCallback, Object, UInt32, Boolean) method.

Se aplica a

Seguridad para subprocesos

Este tipo es seguro para la ejecución de subprocesos.This type is thread safe.

Consulte también: