BackgroundWorker.ReportProgress Método

Definición

Genera el evento ProgressChanged.

Sobrecargas

ReportProgress(Int32)

Genera el evento ProgressChanged.

ReportProgress(Int32, Object)

Genera el evento ProgressChanged.

ReportProgress(Int32)

Genera el evento ProgressChanged.

public:
 void ReportProgress(int percentProgress);
public void ReportProgress (int percentProgress);
member this.ReportProgress : int -> unit
Public Sub ReportProgress (percentProgress As Integer)

Parámetros

percentProgress
Int32

Porcentaje, de 0 a 100, de la operación en segundo plano que se ha completado.

Excepciones

La propiedad WorkerReportsProgress está establecida en false.

Ejemplos

En el ejemplo de código siguiente se muestra el uso del ReportProgress método para notificar el progreso de una operación asincrónica al usuario. Este ejemplo de código es parte de un ejemplo más grande proporcionado para la clase BackgroundWorker.

// Abort the operation if the user has cancelled.
// Note that a call to CancelAsync may have set 
// CancellationPending to true just after the
// last invocation of this method exits, so this 
// code will not have the opportunity to set the 
// DoWorkEventArgs.Cancel flag to true. This means
// that RunWorkerCompletedEventArgs.Cancelled will
// not be set to true in your RunWorkerCompleted
// event handler. This is a race condition.
if ( worker->CancellationPending )
{
   e->Cancel = true;
}
else
{
   if ( n < 2 )
   {
      result = 1;
   }
   else
   {
      result = ComputeFibonacci( n - 1, worker, e ) + ComputeFibonacci( n - 2, worker, e );
   }

   // Report progress as a percentage of the total task.
   int percentComplete = (int)((float)n / (float)numberToCompute * 100);
   if ( percentComplete > highestPercentageReached )
   {
      highestPercentageReached = percentComplete;
      worker->ReportProgress( percentComplete );
   }
}
// Abort the operation if the user has canceled.
// Note that a call to CancelAsync may have set 
// CancellationPending to true just after the
// last invocation of this method exits, so this 
// code will not have the opportunity to set the 
// DoWorkEventArgs.Cancel flag to true. This means
// that RunWorkerCompletedEventArgs.Cancelled will
// not be set to true in your RunWorkerCompleted
// event handler. This is a race condition.

if (worker.CancellationPending)
{   
    e.Cancel = true;
}
else
{   
    if (n < 2)
    {   
        result = 1;
    }
    else
    {   
        result = ComputeFibonacci(n - 1, worker, e) + 
                 ComputeFibonacci(n - 2, worker, e);
    }

    // Report progress as a percentage of the total task.
    int percentComplete = 
        (int)((float)n / (float)numberToCompute * 100);
    if (percentComplete > highestPercentageReached)
    {
        highestPercentageReached = percentComplete;
        worker.ReportProgress(percentComplete);
    }
}
' Abort the operation if the user has canceled.
' Note that a call to CancelAsync may have set 
' CancellationPending to true just after the
' last invocation of this method exits, so this 
' code will not have the opportunity to set the 
' DoWorkEventArgs.Cancel flag to true. This means
' that RunWorkerCompletedEventArgs.Cancelled will
' not be set to true in your RunWorkerCompleted
' event handler. This is a race condition.
If worker.CancellationPending Then
    e.Cancel = True
Else
    If n < 2 Then
        result = 1
    Else
        result = ComputeFibonacci(n - 1, worker, e) + _
                 ComputeFibonacci(n - 2, worker, e)
    End If

    ' Report progress as a percentage of the total task.
    Dim percentComplete As Integer = _
        CSng(n) / CSng(numberToCompute) * 100
    If percentComplete > highestPercentageReached Then
        highestPercentageReached = percentComplete
        worker.ReportProgress(percentComplete)
    End If

End If

Comentarios

Si necesita la operación en segundo plano para informar sobre su progreso, puede llamar al ReportProgress método para generar el ProgressChanged evento. El WorkerReportsProgress valor de la propiedad debe ser true, o ReportProgress producirá una InvalidOperationExceptionexcepción .

Es necesario implementar una manera significativa de medir el progreso de la operación en segundo plano como un porcentaje de la tarea total completada.

La llamada al ReportProgress método es asincrónica y devuelve inmediatamente. El ProgressChanged controlador de eventos se ejecuta en el subproceso que creó .BackgroundWorker

Consulte también

Se aplica a

ReportProgress(Int32, Object)

Genera el evento ProgressChanged.

public:
 void ReportProgress(int percentProgress, System::Object ^ userState);
public void ReportProgress (int percentProgress, object userState);
public void ReportProgress (int percentProgress, object? userState);
member this.ReportProgress : int * obj -> unit
Public Sub ReportProgress (percentProgress As Integer, userState As Object)

Parámetros

percentProgress
Int32

Porcentaje, de 0 a 100, de la operación en segundo plano que se ha completado.

userState
Object

Objeto Object único que indica el estado del usuario. Se devuelve como la propiedad UserState de ProgressChangedEventArgs.

Excepciones

La propiedad WorkerReportsProgress está establecida en false.

Ejemplos

En el ejemplo de código siguiente se muestra el uso del ReportProgress método para notificar el progreso de una operación asincrónica al usuario. Este ejemplo de código es parte de un ejemplo más grande proporcionado para la clase ToolStripProgressBar.

private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
    // This method will run on a thread other than the UI thread.
    // Be sure not to manipulate any Windows Forms controls created
    // on the UI thread from this method.
    backgroundWorker.ReportProgress(0, "Working...");
    Decimal lastlast = 0;
    Decimal last = 1;
    Decimal current;
    if (requestedCount >= 1)
    { AppendNumber(0); }
    if (requestedCount >= 2)
    { AppendNumber(1); }
    for (int i = 2; i < requestedCount; ++i)
    {
        // Calculate the number.
        checked { current = lastlast + last; }
        // Introduce some delay to simulate a more complicated calculation.
        System.Threading.Thread.Sleep(100);
        AppendNumber(current);
        backgroundWorker.ReportProgress((100 * i) / requestedCount, "Working...");
        // Get ready for the next iteration.
        lastlast = last;
        last = current;
    }

    backgroundWorker.ReportProgress(100, "Complete!");
}
Private Sub backgroundWorker1_DoWork(sender As Object, e As DoWorkEventArgs)
   ' This method will run on a thread other than the UI thread.
   ' Be sure not to manipulate any Windows Forms controls created
   ' on the UI thread from this method.
   backgroundWorker.ReportProgress(0, "Working...")
   Dim lastlast As [Decimal] = 0
   Dim last As [Decimal] = 1
   Dim current As [Decimal]
   If requestedCount >= 1 Then
      AppendNumber(0)
   End If
   If requestedCount >= 2 Then
      AppendNumber(1)
   End If
   Dim i As Integer
   
   While i < requestedCount
      ' Calculate the number.
      current = lastlast + last
      ' Introduce some delay to simulate a more complicated calculation.
      System.Threading.Thread.Sleep(100)
      AppendNumber(current)
      backgroundWorker.ReportProgress(100 * i / requestedCount, "Working...")
      ' Get ready for the next iteration.
      lastlast = last
      last = current
      i += 1
   End While
   
   
   backgroundWorker.ReportProgress(100, "Complete!")
 End Sub

Comentarios

Si necesita la operación en segundo plano para informar sobre su progreso, puede llamar al ReportProgress método para generar el ProgressChanged evento. El WorkerReportsProgress valor de la propiedad debe true, o ReportProgress producirá una InvalidOperationExceptionexcepción .

Es necesario implementar una manera significativa de medir el progreso de la operación en segundo plano como un porcentaje de la tarea total completada.

Consulte también

Se aplica a