Visual Basic.NET - Background Worker + Delegados + Clases

Private Sub BtnSincroniza_Click(sender As Object, e As EventArgs) Handles BtnSincroniza.Click

        ProgressBar1.Visible = True

        Dim Ejecuta As New ClasedetuBackgroundWorker

        Ejecuta.TuWorker.RunWorkerAsync() 'ejecutas el backgroundworker

End Sub

Public Class ClasedetuBackgroundWorker

        Public WithEvents TuWorker As New BackgroundWorker

        Dim i as integer=0

Private Sub TuWorker_DoWork(ByVal sender As Object, ByVal e As DoWorkEventArgs) Handles TuWorker.DoWork

        'El DoWork, aqui es donde haces todo lo que necesites que se haga en segundo plano.

         'por ejemplo:

         Form1.ProgressBar1.Minimum = 0

         Form1.ProgressBar1.Maximum = 100

         for i =1 blablabla...

                TuWorker.ReportProgress(i) 'con esto envias el progreso a la progressbar en la propiedad del ProgressChanged

                i++

         next

End Sub

Private Sub TuWorker_ProgressChanged(ByVal sender As Object, ByVal e As ProgressChangedEventArgs) Handles TuWorker.ProgressChanged

        'Aqui en la propiedad del ProgressChanged es donde ves por ejemplo la progressbar mientras se ejecuta el DoWork, ejemplo:

            Form1.ProgressBar1.Value = e.ProgressPercentage

End Sub

Private Sub TuWorker_RunWorkerCompleted(ByVal sender As Object, ByVal e As RunWorkerCompletedEventArgs) Handles TuWorker.RunWorkerCompleted

        'Con RunWorkerCompleted manejas cuando termina de ejecutarse el DoWork

End Sub

End Class