BackgroundWorker.ReportProgress Method (Int32, Object)
Raises the ProgressChanged event.
Assembly: System (in System.dll)
'Declaration Public Sub ReportProgress ( _ percentProgress As Integer, _ userState As Object _ )
If you need the background operation to report on its progress, you can call the ReportProgress method to raise the ProgressChanged event. The WorkerReportsProgress property value must true, or ReportProgress will throw an InvalidOperationException.
It is up to you to implement a meaningful way of measuring your background operation's progress as a percentage of the total task completed.
The following code example demonstrates the use of the ReportProgress method to report the progress of an asynchronous operation to the user. This code example is part of a larger example provided for the ToolStripProgressBar class.
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
Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.