C# 串口通信

我们知道对于 

 

 标准DLL,可以采用DllImport进行调用。例如：

 [DllImport("KMY350X.dll")]
        private static extern int OpenPort(int PortNum, int BaudRate);

　　

如果一些厂家比较懒的话，没有提供相应的dll,我们只能对它进行串口通信编程了。以前从没接触过串口编程，最近在一个项目中有几个地方都需要采用串口通信，跟公司一个老手请教后，感觉学到了很多东西，特在此做个总结:

     

 一：首先我们来认识下什么是串口：

右键 我的电脑-管理-设备管理器-端口，选择一个端口，点击属性。

        

我们可以看到该串口的属性，在C#中我们使用SerialPort类来表示串口

 

           ConfigClass config = new ConfigClass();
           comm.serialPort.PortName = config.ReadConfig("SendHealCard");
            //波特率
            comm.serialPort.BaudRate = 9600;
            //数据位
            comm.serialPort.DataBits = 8;
            //两个停止位
            comm.serialPort.StopBits = System.IO.Ports.StopBits.One;
            //无奇偶校验位
            comm.serialPort.Parity = System.IO.Ports.Parity.None;
            comm.serialPort.ReadTimeout = 100;
            comm.serialPort.WriteTimeout = -1;

　　

   二：串口调试工具：

在对串口进行编程时候，我们要向串口发送指令，然后我们解析串口返回的指令。在这里向大家推荐一款工具。

        串口调试助手.exe

        

         

将要发送的指令用空格隔开，选择HEX显示为放回的字符串。

三：正式编程：

       

编写Comm类:

 public class Comm   
     {
        public delegate void EventHandle(byte[] readBuffer);
        public event EventHandle DataReceived;

        public SerialPort serialPort;
        Thread thread;
        volatile bool _keepReading;

        public Comm()
        {
            serialPort = new SerialPort();
            thread = null;
            _keepReading = false;
        }

        public bool IsOpen
        {
            get 
            {
                return serialPort.IsOpen;
            }
        }        

        private void StartReading()
        {
            if (!_keepReading)
            {
                _keepReading = true;
                thread = new Thread(new ThreadStart(ReadPort));
                thread.Start();
            }
        }

        private void StopReading()
        {
            if (_keepReading)
            {
                _keepReading = false;
                thread.Join();
                thread = null;                
            }
        }

        private void ReadPort()
        {
            while (_keepReading)
            {
                if (serialPort.IsOpen)
                {
                    int count = serialPort.BytesToRead;
                    if (count > 0)
                    {
                        byte[] readBuffer = new byte[count];
                        try
                        {
                            Application.DoEvents();
                            serialPort.Read(readBuffer, 0, count);
                            if(DataReceived != null)
                                DataReceived(readBuffer);
                            Thread.Sleep(100);
                        }
                        catch (TimeoutException)
                        {
                        }
                    }
                }
            }
        }

        public void Open()
        {
            Close();            
            serialPort.Open();
            if (serialPort.IsOpen)
            {
                StartReading();
            }
            else
            {
                MessageBox.Show("串口打开失败！");
            }
        }

        public void Close()
        {
            StopReading();
            serialPort.Close();
        }

        public void WritePort(byte[] send, int offSet, int count)
        {
            if (IsOpen)
            {
                serialPort.Write(send, offSet, count);
            }
        }
    }

注册串口：

            Comm    comm = new Comm();
            ConfigClass config = new ConfigClass();
            comm.serialPort.PortName = config.ReadConfig("SendHealCard");
            //波特率
            comm.serialPort.BaudRate = 9600;
            //数据位
            comm.serialPort.DataBits = 8;
            //两个停止位
            comm.serialPort.StopBits = System.IO.Ports.StopBits.One;
            //无奇偶校验位
            comm.serialPort.Parity = System.IO.Ports.Parity.None;
            comm.serialPort.ReadTimeout = 100;
             comm.serialPort.WriteTimeout = -1; 
     
            comm.Open();
            if (comm.IsOpen)
            {
                comm.DataReceived += new Comm.EventHandle(comm_DataReceived);
            }

　　

发送指令：

        /// <summary>
        /// 发卡到机口
        /// </summary>
        private void SendCardToOut()
        {
            is_read_card = false;
            sendCardToOut = true;
            byte[] send = { 0x02, 0x46, 0x43, 0x34, 0x03, 0x30 };
            if (comm.IsOpen)
            {
                comm.WritePort(send, 0, send.Length);
            }
        } 

　　

收到指令，并解析：

void comm_DataReceived(byte[] readBuffer1)
 {
            //log.Info(HexCon.ByteToString(readBuffer));
            if (readBuffer1.Length == 1)
            {
                receive = HealCardClass.ByteToString(readBuffer1);
                string str = "06";
                if (string.Equals(receive.Trim(), str, StringComparison.CurrentCultureIgnoreCase))
                {
                    try
                    {
                        if (is_read_card)
                        {
                            byte[] send = new byte[1];
                            send[0] = 0x05;
                            comm.WritePort(send, 0, send.Length);
                            Thread.Sleep(500);
                            comm.DataReceived -= new Comm.EventHandle(comm_DataReceived);
                            InitReadComm();
                        }
                        if (sendCardToOut)
                        {
                            byte[] send = new byte[1];
                            send[0] = 0x05;
                            comm.WritePort(send, 0, send.Length);


                            readComm.DataReceived -= new Comm.EventHandle(readComm_DataReceived);
                            readComm.Close();

                            log.Info("发卡完成！");
                            lblMsg.Text = "发卡成功！";
                            lblSendCardMsg.Text = "发卡完成，请收好卡！";
                            timer1.Tick -= new EventHandler(timer1_Tick);
                            PlaySound();
                            this.btnOK.Enabled = true;


                        }
                    }
                    catch (Exception ex)
                    {
                        log.Info(ex.ToString());
                    }
                }
            }
  } 

到此：串口通讯，发送数据，接收数据就完成了。