//获取系统中的串口并加入到下拉框中

            cbCashBoxPort.Items.Clear();

            string[] ports = System.IO.Ports.SerialPort.GetPortNames();

            if (ports != null)

            {

                foreach (string port in ports)

                {

                    cbCashBoxPort.AddItem(port, port);

                }

            }

            //获取系统中的并口并加入到下拉框中

            using (ManagementObjectSearcher seacher = new ManagementObjectSearcher("select * from Win32_ParallelPort"))

            {

                foreach (ManagementObject item in seacher.Get())

                {

                        PropertyData data = item.Properties["Caption"];

                        cbCashBoxPort.AddItem(data.Value.ToString(),data.Value.ToString());

                }

            }