CrusherScanner/crusherScanner/SerialAccess.cs

using System.IO.Ports;

namespace crusherScanner
{
    /// <summary>
    /// For sending data to Prepmaster via serial.
    /// nb; The concept here is to NOT hold the serial port open.
    /// </summary>
    internal class SerialAccess
    {

        private static bool SerialReady = false;
        private static SerialPort? _serialPort;

        /// <summary>
        /// Send sample ID to the serial port for Prepmaster to receive.
        /// </summary>
        /// <param name="barcode">The sample ID to send.</param>
        public static void SendToPrepmaster(string barcode)
        {
            if (barcode != "" && !Properties.Settings.Default.PrepmasterConnection)
            {
                MessageBox.Show($"The crusher flap would\nhave just opened to\naccept sample {barcode}", "Crusher Input");
            }
            else if (barcode != "")
            {
                if (!SerialReady)
                {
                    SetupSerial();
                }
                SendSerial(barcode);
            }
        }

        /// <summary>
        /// Setup and test the serial port.
        /// </summary>
        private static void SetupSerial()
        {
            //TODO: use settings for connection
            _serialPort = new SerialPort("COM1", 19200, Parity.None, 8, StopBits.One);
            _serialPort.Handshake = Handshake.None;

            try
            {
                // Opens serial port as a quick test
                _serialPort.Open();
            }
            catch (Exception ex)
            {
                Logging.Append("Error opening serial port :: " + ex.Message);
                MessageBox.Show("Error opening serial port :: " + ex.Message, "Error!");
            }
            finally
            {
                _serialPort.Close();
                SerialReady = true;
            }
        }

        /// <summary>
        /// Send data to the serial connection.
        /// </summary>
        /// <param name="data">The sample ID to send to Prepmaster.</param>
        private static void SendSerial(string data)
        {

            if (_serialPort == null)
            {
                Logging.Append("Error opening serial port :: _serialPort is null");
                MessageBox.Show("Error opening serial port :: Serial device may have been unpluged.", "Error!");
                SerialReady = false;
                return;
            }

            // Makes sure serial port is open before trying to write  
            try
            {
                if (!_serialPort.IsOpen)
                {
                    _serialPort.Open();
                    _serialPort.Write(data + "\r\n");
                }
            }
            catch (Exception ex)
            {
                Logging.Append("Error opening serial port :: " + ex.Message);
                MessageBox.Show("Error opening/writing to serial port :: " + ex.Message, "Error!");
            }
        }

    }
}