' This delegate enables asynchronous calls for setting
    ' the text property on a TextBox control.
    Delegate Sub SetTextCallback(ByVal Value As String)

 
   Private Sub SetText(ByVal Value As String)
        Dim s As String = Me.txtOUT.Text

        ' InvokeRequired required compares the thread ID of the
        ' calling thread to the thread ID of the creating thread.
        ' If these threads are different, it returns true.
        If Me.txtOUT.InvokeRequired Then
            Dim d As New SetTextCallback(AddressOf SetText)
            Me.Invoke(d, New Object() {Value})
        Else
            Me.txtOUT.Text = s & Value & vbCrLf
            Me.txtOUT.SelectionStart = Me.txtOUT.TextLength
        End If
    End Sub