C#串口操作實用類

 

        做工業通訊有很長時間了，特別是串口（232/485)，有VB/VC/C各種版本的串口作業碼，這些代碼也經過了多年的現場考驗，應該說是比較健壯的代碼，但是目前卻沒有C#相對成熟的串口作業碼，最近用Moxa的裝置開發基於WinCE5.0的串口作業碼，所以就擴充完善了一下串口操作，特別是SendCommand函數，這是我比較常用的主從通訊代碼，不喜歡用事件或線程接資料，在規定的逾時時間內直接迴圈判斷要接收的資料。

     下面是具體的代碼：   

 

  public class PortData
    {
        public event PortDataReceivedEventHandle Received;
        public event SerialErrorReceivedEventHandler Error; 
        public SerialPort port;
        public bool ReceiveEventFlag = false;  //接收事件是否有效 false表示有效

        public PortData(string sPortName, int baudrate,Parity parity,SerialInterface.SerialMode mode)
        {
            port = new SerialPort(sPortName, baudrate, parity, 8, StopBits.One);
            port.RtsEnable = true;
            port.ReadTimeout = 3000;
            port.DataReceived += new SerialDataReceivedEventHandler(DataReceived);
            port.ErrorReceived += new SerialErrorReceivedEventHandler(ErrorEvent);
        }

        ~PortData()
        {
            Close();
        }
        public void Open()
        {
            if (!port.IsOpen)
            {           
                port.Open();
            }
        }

        public void Close()
        {
            if (port.IsOpen)
            {
                port.Close();
            }
        }
        //資料發送
        public void SendData(byte[] data)
        {
            if (port.IsOpen)
            {
                port.Write(data, 0, data.Length);
            }
        }
        public void SendData(byte[] data,int offset,int count)
        {
            if (port.IsOpen)
            {
                port.Write(data, offset, count);
            }
        }
        //發送命令
        public int SendCommand(byte[] SendData, ref  byte[] ReceiveData,int Overtime)
        {

            if(port.IsOpen)
            {
                ReceiveEventFlag = true;        //關閉接收事件
                port.DiscardInBuffer();         //清空接收緩衝區                 
                port.Write(SendData, 0, SendData.Length);
                int num=0,ret=0;
                while (num++ < Overtime)
                {
                    if (port.BytesToRead >= ReceiveData.Length) break;
                    System.Threading.Thread.Sleep(1); 
                }
                if (port.BytesToRead >= ReceiveData.Length) 
                    ret = port.Read(ReceiveData, 0, ReceiveData.Length);
                ReceiveEventFlag = false;       //開啟事件
                return ret;
            }
            return -1;
        }

        public void ErrorEvent(object sender, SerialErrorReceivedEventArgs e)
        {
            if (Error != null) Error(sender, e);
        }
        //資料接收
        public void DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
            //禁止接收事件時直接退出
            if (ReceiveEventFlag) return;

            byte[] data = new byte[port.BytesToRead];
            port.Read(data, 0, data.Length);
            if (Received != null) Received(sender, new PortDataReciveEventArgs(data));
        }

        public bool IsOpen()
        {
            return port.IsOpen;
        }
    }
    public delegate void PortDataReceivedEventHandle(object sender, PortDataReciveEventArgs e);
    public class PortDataReciveEventArgs : EventArgs
    {
        public PortDataReciveEventArgs()
        {
            this.data = null;
        }

        public PortDataReciveEventArgs(byte[] data)
        {
            this.data = data;
        }

        private byte[] data;

        public byte[] Data
        {
            get { return data; }
            set { data = value; }
        }
    }

 

【附註】1~9 串口的名稱是 "COMx:",>9的以前用\\\\.\\COMx:比較好使，但是在moxa 661裝置上卻不行，要用如下格式"$device\\COM" + PortNo.ToString() + "\0"，也許這是moxa修改了相應的串口驅動。