监测串口通讯状态

1、监测串口通讯状态

namespace CheckPLC
{
    public partial class Form1 : Form
    {
        SerialPort plc = new SerialPort("COM2", 9600, Parity.Odd, 8, StopBits.One);
        System.Timers.Timer Timer1 = new System.Timers.Timer(5000);


        public Form1()
        {
            InitializeComponent();
        }


        private void Form1_Load(object sender, EventArgs e)
        {
            plc.DataReceived += new SerialDataReceivedEventHandler(plc_DataReceived);
            plc.Open();


            Timer1.Elapsed += new System.Timers.ElapsedEventHandler(CheckPlc);
            Timer1.AutoReset = true;
            Timer1.Enabled = true;
        }


        private void plc_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            byte[] readBuffer = new byte[plc.ReadBufferSize];
            plc.Read(readBuffer, 0, readBuffer.Length);
            string readstr = Encoding.UTF8.GetString(readBuffer);


            if (readstr.Substring(0,2) == "ok")
            {
                Timer1.Enabled = false;
                Timer1.Enabled = true;
            }


            //MessageBox.Show(readstr);//调试用
        }


        public void CheckPlc(Object source, System.Timers.ElapsedEventArgs e)
        {
            MessageBox.Show("真是惨，PLC坏了！");
            Timer1.Enabled = false;
        }
    }
}