如何使用 BackGroundWorker 刷新 DataGridView

Question

I'm trying to create an application that receives aa list of file paths and print in sequence all of this files. While printing the files you can cancel printing or move the files within the list. Everything works good but i don't know how to refresh the DataGridView after every update. So please someone could help me? Here is my code, i tried to use BackgroundWorker_ProgressChanged to update the datagridview But I know it's not the best thing to do.

Private Sub btnCancelPrint_Click(sender As Object, e As EventArgs) Handles btnCancelPrint.Click
    Dim msg = "Annullare la stampa di tutti i documenti?"
    Dim title = "Annulla Stampa"
    Dim style = MsgBoxStyle.YesNo Or MsgBoxStyle.DefaultButton2 Or
                MsgBoxStyle.Critical
    Dim response = MsgBox(msg, style, title)
    If response = MsgBoxResult.Yes Then
        If BackgroundWorkerPrint.IsBusy Then
            If BackgroundWorkerPrint.WorkerSupportsCancellation Then
                btnPrint.Enabled = True
                btnCancelPrint.Enabled = False
                BackgroundWorkerPrint.CancelAsync()
            End If
        End If
    End If

End Sub
Private Sub btnPrint_Click(sender As Object, e As EventArgs) Handles btnPrint.Click
    Try
        If BackgroundWorkerPrint.IsBusy <> True Then
            btnPrint.Enabled = False
            BackgroundWorkerPrint.RunWorkerAsync()
        End If
    Catch ex As Exception
    End Try
End Sub
Private Sub BackgroundWorker1_DoWork(sender As Object, e As System.ComponentModel.DoWorkEventArgs) Handles BackgroundWorkerPrint.DoWork
    printFont = New Font("Arial", 10)
    Dim pd As New PrintDocument()
    Dim pDialog As New PrintDialog()
    Dim ps As New PrinterSettings()
    Dim psize As New PaperSize()
    pd.DefaultPageSettings.Landscape = False
    pDialog.Document = pd
    pDialog.Document.DefaultPageSettings.PaperSize = psize
    AddHandler pd.PrintPage, AddressOf PrintDoc_PrintPage
    Dim result As New DialogResult
    result = pDialog.ShowDialog()
    BackgroundWorkerPrint.ReportProgress(0)
    BackgroundWorkerPrint.ReportProgress(4)
    For Each fattura As Fattura In DataGridFatture.DataSource
        Thread.Sleep(10000)
        If BackgroundWorkerPrint.CancellationPending Then
            BackgroundWorkerPrint.ReportProgress(2)
            e.Cancel = True
            Exit For
        End If
        If (fattura.Stato <> Fattura.Semaforo.STAMPATO) Then
            pathDoc = fattura.Path
            BackgroundWorkerPrint.ReportProgress(3)
            Try
                streamToPrint = New StreamReader(fattura.Path)
                Try
                    If (result = DialogResult.OK) Then
                        pd.Print()
                        BackgroundWorkerPrint.ReportProgress(1)
                    End If
                Finally
                    streamToPrint.Close()
                End Try
            Catch ex As Exception
                MessageBox.Show(ex.Message)
            End Try
        End If
    Next
    BackgroundWorkerPrint.ReportProgress(5)
End Sub
Private Sub BackgroundWorkerPrint_ProgressChanged(sender As Object, e As System.ComponentModel.ProgressChangedEventArgs) Handles BackgroundWorkerPrint.ProgressChanged
    Select Case e.ProgressPercentage
        Case 0
            For Each dr As Fattura In DataGridFatture.DataSource
                If (dr.Stato <> Fattura.Semaforo.STAMPATO) Then
                    dr.Stato = Fattura.Semaforo.INATTESA
                    dr.Icon = My.Resources.Waiting_icon
                    DataGridFatture.Refresh()
                End If
            Next
        Case 1
            For Each dr As Fattura In DataGridFatture.DataSource
                If (dr.Path = pathDoc) Then
                    dr.Stato = Fattura.Semaforo.STAMPATO
                    dr.Icon = My.Resources.Ok_Icon
                    DataGridFatture.Refresh()
                End If
            Next
        Case 2
            For Each dr As Fattura In DataGridFatture.DataSource
                If (dr.Stato = Fattura.Semaforo.INSTAMPA Or dr.Stato = Fattura.Semaforo.INATTESA) Then
                    dr.Stato = Fattura.Semaforo.ANNULLATO
                    dr.Icon = My.Resources.Cancel_icon
                    DataGridFatture.Refresh()
                End If
            Next
        Case 3
            For Each dr As Fattura In DataGridFatture.DataSource
                If (dr.Path = pathDoc) Then
                    dr.Stato = Fattura.Semaforo.INSTAMPA
                    dr.Icon = My.Resources.Print_icon
                    DataGridFatture.Refresh()
                End If
            Next
        Case 4
            btnCancelPrint.Enabled = True
        Case 5
            btnPrint.Enabled = True
    End Select
End Sub

Private Sub btnDown_Click(sender As Object, e As EventArgs) Handles btnDown.Click
    If (bs.Count <= 1) Then Return

    Dim position As Integer = bs.Position
    If (position = bs.Count - 1) Then Return

    bs.RaiseListChangedEvents = False

    Dim current As Fattura = bs.Current
    bs.Remove(current)

    position = position + 1

    bs.Insert(position, current)
    bs.Position = position

    bs.RaiseListChangedEvents = True
    bs.ResetBindings(False)
End Sub

Answer 1

The problem is that the datagrid doesn't belong to the background process but it's got to another process, your form. Background process has its own resources and cannot access directly to the form controls, Anyway: try with:

System.Windows.Forms.Control.CheckForIllegalCrossThreadCalls = false

but attention, this instruction breaks the security policy.