Option Strict On
 
Public Class WorkerState
    Public Property ProgressPIValue As Double
    Public Property ProgressPILoop As Single
    Public Property InfoText As String
End Class
 
Public Class clsThreadTest
 
    Private WithEvents WORKER As New System.ComponentModel.BackgroundWorker
 
    Public Event NewINfo(ByVal InfoNr As Integer, ByVal ws As WorkerState)
 
    Public Sub StartScan()
        Me.WORKER.WorkerReportsProgress = True
        Me.WORKER.WorkerSupportsCancellation = True
        Me.WORKER.RunWorkerAsync()
    End Sub
 
    Public Sub CancelScan()
        If Me.WORKER.IsBusy Then
            Me.WORKER.CancelAsync()
        End If
    End Sub
 
    Private Sub worker_DoWork(ByVal sender As Object, ByVal e As  _
      System.ComponentModel.DoWorkEventArgs) Handles WORKER.DoWork
 
        Dim I As Integer
        Dim j As Single
 
        Dim ws As New WorkerState
        ws.ProgressPIValue = 0
        ws.Infotext = CStr(Now) & " - Start"
        WORKER.ReportProgress(0, ws)
 
        For I = 1 To 100
 
 
            WORKER.ReportProgress(I, ws)
 
            Dim PI As Double = 0
            For j = 1 To 400
                PI = 0
                For ii As Integer = 0 To 100
                    PI += 1 / Math.Pow(16, ii) * (4 / ((8 * ii) + 1) - 2 / ((8 _
                      * ii) + 4) - 1 / ((8 * ii) + 5) - 1 / ((8 * ii) + 6))
                Next
 
                ws.InfoText = ""
                ws.ProgressPIValue = PI
                ws.ProgressPILoop = j
                WORKER.ReportProgress(I, ws)
            Next
 
            If WORKER.CancellationPending = True Then Exit For
 
        Next
 
        ws.Infotext = CStr(Now) & " - Ende"
        WORKER.ReportProgress(100, ws)
    End Sub
 
    Private Sub worker_ProgressChanged(ByVal sender As Object, ByVal e As  _
      System.ComponentModel.ProgressChangedEventArgs) Handles _
      WORKER.ProgressChanged
        RaiseEvent NewINfo(e.ProgressPercentage, CType(e.UserState, _
          WorkerState))
    End Sub
 
End Class

  Private Sub Scan1_NewINfo(ByVal ProgressPercentage As Integer, _
      ByVal ws As BGW_Test.WorkerState) Handles Scan1.NewINfo
 
        lblinfo_loop1.Text = CStr(ProgressPercentage)
        lblinfo_loop2.Text = CStr(ws.ProgressPILoop) & ":  " & CStr( _
          ws.ProgressPIValue)
        If Not String.IsNullOrEmpty(ws.InfoText) Then
            rtblog.AppendText(ws.InfoText & vbCrLf)
        End If
    End Sub