public partial class Form1 : Form
    {
        /// <summary>
        /// 接受数据的串口类 
        /// </summary>
        SerialPort spReceive;
        delegate void ReceivData(byte[] bytes);

public Form1()
        {
            Form1.CheckForIllegalCrossThreadCalls = false;
            InitializeComponent();
          
            spReceive =new SerialPort("COM5", 57600, Parity.None, 8, StopBits.One);             
            spReceive.Open();
            
            //设置触发 DataReceived事件的阀值,在调试中发现这个不起作用，不解~      
            spReceive.ReceivedBytesThreshold =15;            
            spReceive.DataReceived +=new System.IO.Ports.SerialDataReceivedEventHandler(spReceive_DataReceived);            
        }

/// <summary>
        /// 更新接受到得数据到UI 界面显示
        /// </summary>
        /// <param name="bytes"></param>
        public void UpdateReceiveToUI(byte[] bytes)
        {
            if (txtReceive.InvokeRequired)
            {
                ReceivData dl = new ReceivData(UpdateReceiveToUI);
                object arg = bytes;
                txtReceive.Invoke(dl, arg);
            }
            else
                txtReceive.Text += "/" + BitConverter.ToString(bytes);
        }

/// <summary>
        /// 接收到串口数据触发的事 件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        public void spReceive_DataReceived(object sender, System.IO.Ports.SerialDataReceivedEventArgs e)
        {
            byte[] recevied = new byte[15];
            int size = spReceive.Read(recevied, 0, recevied.Length);