private void AddLog(String Message) { if (this.rtb_log.InvokeRequired) { AddlogEventHandler evt = new AddlogEventHandler(AddLog); this.Invoke(evt, new object[] { Message }); } else { if (Message == null) { this.rtb_log.AppendText("Device not connected."); } else { this.rtb_log.AppendText(":" + Message); } } }