PageAsyncTask.EndHandler Propiedad
Definición
Importante
Parte de la información hace referencia a la versión preliminar del producto, que puede haberse modificado sustancialmente antes de lanzar la versión definitiva. Microsoft no otorga ninguna garantía, explícita o implícita, con respecto a la información proporcionada aquí.
Obtiene el método al que se debe llamar cuando la tarea se lleva a cabo correctamente en el período del tiempo de espera.
public:
property System::Web::EndEventHandler ^ EndHandler { System::Web::EndEventHandler ^ get(); };
public System.Web.EndEventHandler EndHandler { get; }
member this.EndHandler : System.Web.EndEventHandler
Public ReadOnly Property EndHandler As EndEventHandler
Valor de propiedad
Delegado de EndEventHandler que representa el método al que se debe llamar cuando la tarea se lleva a cabo correctamente en el período del tiempo de espera.
Ejemplos
En el ejemplo de código siguiente se registran tres tareas asincrónicas en una página y se ejecutan en paralelo. Cada tarea llama a un método que simplemente hace que el subproceso entre en suspensión durante 5 segundos. Se especifica un EndHandler delegado para cada tarea.
<%@ Page Language="C#" Async="true" AsyncTimeout="35"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
protected void Page_Load(object sender, EventArgs e)
{
// Define the asynchronuous task.
Samples.AspNet.CS.Controls.SlowTask slowTask1 =
new Samples.AspNet.CS.Controls.SlowTask();
Samples.AspNet.CS.Controls.SlowTask slowTask2 =
new Samples.AspNet.CS.Controls.SlowTask();
Samples.AspNet.CS.Controls.SlowTask slowTask3 =
new Samples.AspNet.CS.Controls.SlowTask();
// <Snippet3>
PageAsyncTask asyncTask1 = new PageAsyncTask(slowTask1.OnBegin, slowTask1.OnEnd, slowTask1.OnTimeout, "Async1", true);
PageAsyncTask asyncTask2 = new PageAsyncTask(slowTask2.OnBegin, slowTask2.OnEnd, slowTask2.OnTimeout, "Async2", true);
PageAsyncTask asyncTask3 = new PageAsyncTask(slowTask3.OnBegin, slowTask3.OnEnd, slowTask3.OnTimeout, "Async3", true);
// Register the asynchronous task.
Page.RegisterAsyncTask(asyncTask1);
Page.RegisterAsyncTask(asyncTask2);
Page.RegisterAsyncTask(asyncTask3);
// </Snippet3>
// Execute the register asynchronous task.
Page.ExecuteRegisteredAsyncTasks();
TaskMessage.InnerHtml = slowTask1.GetAsyncTaskProgress()+ "<br />" + slowTask2.GetAsyncTaskProgress() + "<br />" + slowTask3.GetAsyncTaskProgress();
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>Asynchronous Task Example</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<span id="TaskMessage" runat="server">
</span>
</div>
</form>
</body>
</html>
<%@ Page Language="VB" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
' Define the asynchronuous task.
Dim slowTask1 As New Samples.AspNet.VB.Controls.SlowTask()
Dim slowTask2 As New Samples.AspNet.VB.Controls.SlowTask()
Dim slowTask3 As New Samples.AspNet.VB.Controls.SlowTask()
' <Snippet3>
Dim asyncTask1 As New PageAsyncTask(AddressOf slowTask1.OnBegin, AddressOf slowTask1.OnEnd, AddressOf slowTask1.OnTimeout, "Async1", True)
Dim asyncTask2 As New PageAsyncTask(AddressOf slowTask2.OnBegin, AddressOf slowTask2.OnEnd, AddressOf slowTask2.OnTimeout, "Async2", True)
Dim asyncTask3 As New PageAsyncTask(AddressOf slowTask3.OnBegin, AddressOf slowTask3.OnEnd, AddressOf slowTask3.OnTimeout, "Async3", True)
' Register the asynchronous task.
Page.RegisterAsyncTask(asyncTask1)
Page.RegisterAsyncTask(asyncTask2)
Page.RegisterAsyncTask(asyncTask3)
' </Snippet3>
' Execute the register asynchronous task.
Page.ExecuteRegisteredAsyncTasks()
TaskMessage.InnerHtml = slowTask1.GetAsyncTaskProgress() + "<br />" + slowTask2.GetAsyncTaskProgress() + "<br />" + slowTask3.GetAsyncTaskProgress()
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<span id="TaskMessage" runat="server">
</span>
</div>
</form>
</body>
</html>
using System;
using System.Web;
using System.Web.UI;
using System.Threading;
namespace Samples.AspNet.CS.Controls
{
public class SlowTask
{
private String _taskprogress;
private AsyncTaskDelegate _dlgt;
// Create delegate.
protected delegate void AsyncTaskDelegate();
public String GetAsyncTaskProgress()
{
return _taskprogress;
}
public void ExecuteAsyncTask()
{
// Introduce an artificial delay to simulate a delayed
// asynchronous task.
Thread.Sleep(TimeSpan.FromSeconds(5.0));
}
// Define the method that will get called to
// start the asynchronous task.
public IAsyncResult OnBegin(object sender, EventArgs e,
AsyncCallback cb, object extraData)
{
_taskprogress = "AsyncTask started at: " + DateTime.Now + ". ";
_dlgt = new AsyncTaskDelegate(ExecuteAsyncTask);
IAsyncResult result = _dlgt.BeginInvoke(cb, extraData);
return result;
}
// Define the method that will get called when
// the asynchronous task is ended.
public void OnEnd(IAsyncResult ar)
{
_taskprogress += "AsyncTask completed at: " + DateTime.Now;
_dlgt.EndInvoke(ar);
}
// Define the method that will get called if the task
// is not completed within the asynchronous timeout interval.
public void OnTimeout(IAsyncResult ar)
{
_taskprogress += "AsyncTask failed to complete " +
"because it exceeded the AsyncTimeout parameter.";
}
}
}
Imports System.Threading
Namespace Samples.AspNet.VB.Controls
Public Class SlowTask
Private _taskprogress As String
Private _dlgt As AsyncTaskDelegate
' Create delegate.
Protected Delegate Sub AsyncTaskDelegate()
Public Function GetAsyncTaskProgress() As String
Return _taskprogress
End Function
Public Sub ExecuteAsyncTask()
' Introduce an artificial delay to simulate a delayed
' asynchronous task.
Thread.Sleep(TimeSpan.FromSeconds(5.0))
End Sub
' Define the method that will get called to
' start the asynchronous task.
Public Function OnBegin(ByVal sender As Object, ByVal e As EventArgs, ByVal cb As AsyncCallback, ByVal extraData As Object) As IAsyncResult
_taskprogress = "AsyncTask started at: " + DateTime.Now.ToString + ". "
_dlgt = New AsyncTaskDelegate(AddressOf ExecuteAsyncTask)
Dim result As IAsyncResult = _dlgt.BeginInvoke(cb, extraData)
Return result
End Function
' Define the method that will get called when
' the asynchronous task is ended.
Public Sub OnEnd(ByVal ar As IAsyncResult)
_taskprogress += "AsyncTask completed at: " + DateTime.Now.ToString
_dlgt.EndInvoke(ar)
End Sub
' Define the method that will get called if the task
' is not completed within the asynchronous timeout interval.
Public Sub OnTimeout(ByVal ar As IAsyncResult)
_taskprogress += "AsyncTask failed to complete " + _
"because it exceeded the AsyncTimeout parameter."
End Sub
End Class
End Namespace
Comentarios
El EndHandler delegado se establece en el constructor .