原创 【C#】串口操作实用类

转自：http://blog.csdn.net/yefanqiu/archive/2007/03/27/1543187.aspx

 
做工业通信有很长时间了，特别是串口（232/485)，有VB/VC/C各种版本的串口操作代码，这些代码也经过了多年的现场考验，应该说是比较健壮的
代码，但是目前却没有C#相对成熟的串口操作代码，最近用Moxa的设备开发基于WinCE5.0的串口操作代码，所以就扩充完善了一下串口操作，特别是
SendCommand函数，这是我比较常用的主从通信代码，不喜欢用事件或线程接数据，在规定的超时时间内直接循环判断要接收的数据。

     下面是具体的代码：   

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();
            }
        }
//数据发送
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);
            }
        }
//发送命令
public int SendCommand(byte[] SendData, ref byte[] ReceiveData,int Overtime)
        {
if(port.IsOpen)
            {
                ReceiveEventFlag = true;        //关闭接收事件
                port.DiscardInBuffer();         //清空接收缓冲区                 
                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;       //打开事件
return ret;
            }
return -1;
        }
public void ErrorEvent(object sender, SerialErrorReceivedEventArgs e)
        {
if (Error != null) Error(sender, e);
        }
//数据接收
public void DataReceived(object sender, SerialDataReceivedEventArgs e)
        {
//禁止接收事件时直接退出
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; }
        }
    }

【附注】1~9 串口的名称是 "COMx:",>9的以前用\\\\.\\COMx:比较好使，但是在moxa 661设备上却不行，要用如下格式"$device\\COM" + PortNo.ToString() + "\0"，也许这是moxa修改了相应的串口驱动。