Private Sub WritingMsg(ByVal RTF As RichTextBox, ByVal Data As String, ByVal _
  IsDirectory As Boolean)
Dim start As Int32 = RTF.TextLength
RTF.AppendText(Data & vbCrLf & "-----------------------" & vbCrLf)
RTF.Select(start, RTF.TextLength - start)
  If IsDirectory Then
      RTF.SelectionColor = Color.Blue
  Else
      RTF.SelectionColor = Color.Black
  End If
End Sub