C#.net串口通信详解！

VS.NET2005中SerialPort控件操作详解——C#语言编写（VS 2008基本一致）
      （实例编写的是一个使用SerialPort类进行串口通讯，并读取和接受COM端的数据）
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO.Ports;
namespace SerialPorts
{
    public partial class frm_Main : Form
    {
        #region Public Enumerations
        public enum DataMode { Text, Hex }
        public enum LogMsgType { Incoming, Outgoing, Normal, Warning, Error };
        #endregion
        private Color[] LogMsgTypeColor = { Color.Orange, Color.Green, Color.Black, Color.Blue, Color.Red };
        //禁用和启用程序中各控件的状态
        private void EnableControls()
        {
            // 基于串口的打开与否，设置控件状态
            gbPortSettings.Enabled = !ComPort.IsOpen;
            btns.Enabled = btnstop.Enabled = txtSendData.Enabled = btnSend.Enabled = ComPort.IsOpen;
            if (ComPort.IsOpen) btnOpenPort.Text = "关闭串口";
            else btnOpenPort.Text = "打开串口";
        }
        //初始化组件的数据，为串口提供相关参数
        private void InitializeControlValues()
        {
            cmbParity.Items.Clear(); cmbParity.Items.AddRange(Enum.GetNames(typeof(Parity)));
            cmbStopBits.Items.Clear(); cmbStopBits.Items.AddRange(Enum.GetNames(typeof(StopBits)));
            cmbPortName.Items.Clear();
            foreach (string s in SerialPort.GetPortNames())
                cmbPortName.Items.Add(s);
            cmbPortName.Text = cmbPortName.Items[0].ToString();
            cmbParity.Text = cmbParity.Items[0].ToString();
            cmbStopBits.Text = cmbStopBits.Items[0].ToString();
            cmbDataBits.Text = cmbDataBits.Items[0].ToString();
            cmbParity.Text = cmbParity.Items[0].ToString();
            cmbBaudRate.Text = cmbBaudRate.Items[0].ToString();
            EnableControls();
        }
        //十六进制转换字节数组
        private byte[] HexStringToByteArray(string s)
        {
            s = s.Replace(" ", "");
            byte[] buffer = new byte[s.Length / 2];
            for (int i = 0; i < s.Length; i += 2)
                buffer[i / 2] = (byte)Convert.ToByte(s.Substring(i, 2), 16);
            return buffer;
        }
        //字节数组转换十六进制
        private string ByteArrayToHexString(byte[] data)
        {
            StringBuilder sb = new StringBuilder(data.Length * 3);
            foreach (byte b in data)
                sb.Append(Convert.ToString(b, 16).PadLeft(2, '0').PadRight(3, ' '));
            return sb.ToString().ToUpper();
        }
        //显示数据日志
        private void Log(LogMsgType msgtype, string msg)
        {
            rtfTerminal.Invoke(new EventHandler(delegate
            {
                rtfTerminal.SelectedText = string.Empty;
                rtfTerminal.SelectionFont = new Font(rtfTerminal.SelectionFont, FontStyle.Bold);
                rtfTerminal.SelectionColor = LogMsgTypeColor[(int)msgtype];
                rtfTerminal.AppendText(msg);
                rtfTerminal.ScrollToCaret();
            }));
        }
        //串口发送方式
        #region Local Properties
        private DataMode CurrentDataMode
        {
            get
            {
                if (rbHex.Checked) return DataMode.Hex;
                else return DataMode.Text;
            }
            set
            {
                if (value == DataMode.Text) rbText.Checked = true;
                else rbHex.Checked = true;
            }
        }
        #endregion
        //发送数据
        private void SendData()
        {
            if (CurrentDataMode == DataMode.Text)
            {
                // 发送用户的文本到串口
                ComPort.Write(txtSendData.Text);
                // 将用户的文本显示到数据窗口
                Log(LogMsgType.Outgoing, txtSendData.Text + "\n");
            }
            else
            {
                try
                {
                    // 转换用户十六进制数据到字节数组
                    byte[] data = HexStringToByteArray(txtSendData.Text);
                    // 发送数据到串口
                    ComPort.Write(data, 0, data.Length);
                    // 将用户十六进制数据到数据窗口
                    Log(LogMsgType.Outgoing, ByteArrayToHexString(data) + "\n");
                }
                catch (FormatException)
                {
                    // 转换错误
                    Log(LogMsgType.Error, "十六进制数据有误: " + txtSendData.Text + "\n");
                }
            }
            txtSendData.SelectAll();
        }
        /// <summary>
        /// -------------------------------------------------------------
        /// </summary>
        public frm_Main()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            InitializeControlValues();
            ComPort.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived);
        }
        //打开串口
        private void btnOpenPort_Click(object sender, EventArgs e)
        {
            if (ComPort.IsOpen) ComPort.Close();
            else
            {
                //设置串口参数
                ComPort.BaudRate = int.Parse(cmbBaudRate.Text);
                ComPort.DataBits = int.Parse(cmbDataBits.Text);
                ComPort.StopBits = (StopBits)Enum.Parse(typeof(StopBits), cmbStopBits.Text);
                ComPort.Parity = (Parity)Enum.Parse(typeof(Parity), cmbParity.Text);
                ComPort.PortName = cmbPortName.Text;
                // 打开串口
                ComPort.Open();
            }
            // 改变组件状态
            EnableControls();
            // 如果串口打开，将焦点放入txtSendData
            if (ComPort.IsOpen) txtSendData.Focus();
        }
        private void rbHex_CheckedChanged(object sender, EventArgs e)
        {
            if (rbHex.Checked) CurrentDataMode = DataMode.Hex;
        }
        private void rbText_CheckedChanged(object sender, EventArgs e)
        {
            if (rbText.Checked) CurrentDataMode = DataMode.Text;
        }
        //接收数据
        private void port_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {          
            // 判断用户用的是字节模式还是字符模式
            if (CurrentDataMode == DataMode.Text)
            {
                // 读取缓冲区的数据
                string data = ComPort.ReadExisting();
                // 显示读取的数据到数据窗口
                Log(LogMsgType.Incoming, data + "\n");
            }
            else
            {
                // 获取字节长度
                int bytes = ComPort.BytesToRead;
                // 创建字节数组
                byte[] buffer = new byte[bytes];
                // 读取缓冲区的数据到数组
                ComPort.Read(buffer, 0, bytes);
                // 显示读取的数据到数据窗口
                Log(LogMsgType.Incoming, ByteArrayToHexString(buffer) + "\n");
            }
        }
        //发送数据按键
        private void btnSend_Click(object sender, EventArgs e)
        {
            SendData();
        }
        private void lnkAbout_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
        {
            (new frmAbout()).ShowDialog(this);
        }
        //时间组件控制发送数据
        private void timer1_Tick(object sender, EventArgs e)
        {
            SendData();
        }
        //连续发送数据
        private void button1_Click(object sender, EventArgs e)
        {
            delay.Enabled = true;
            btns.Enabled = !delay.Enabled;
            btnstop.Enabled = delay.Enabled;
        }
        //停止连续发送数据
        private void button2_Click(object sender, EventArgs e)
        {
            delay.Enabled = false;
            btns.Enabled = !delay.Enabled;
            btnstop.Enabled = delay.Enabled;
        }
    }
}