serialPort 接收事件不触发及接收长数据

这里关注两个问题：

1、DataReceived 不能触发问题

2、接收大于8的数据分段发回的问题

public static bool OpenDeviceCOM(string portName)
{
    try
    {
        DeviceCOM = new SerialPort();
        DeviceCOM.PortName = portName;
        DeviceCOM.BaudRate = 19200;
        DeviceCOM.Parity = System.IO.Ports.Parity.None;
        DeviceCOM.DataBits = 8;
        DeviceCOM.StopBits = StopBits.One;
        DeviceCOM.ReadTimeout = 1000;
        DeviceCOM.RtsEnable = true;
        DeviceCOM.ReceivedBytesThreshold = 1;
        DeviceCOM.DataReceived += new SerialDataReceivedEventHandler(DeviceCOM_DataReceived);
        DeviceCOM.Open();
        if (DeviceCOM.IsOpen)
            IsDeviceCOMOpen = true;
        return true;
    }
    catch (Exception xcptn)
    {
        CLogManager.SendException(new System.Diagnostics.StackTrace(new System.Diagnostics.StackFrame(true)), xcptn);
        return false;
    }
}

将DeviceCOM.ReceivedBytesThreshold = 1;是解决事件不触发的办法之一。

private static void DeviceCOM_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
    byte[] rcvBytes = null;
    rcvBytes = CSerialPortIO.ReadDeviceCOMBytes();
    ThreadPool.QueueUserWorkItem(new WaitCallback((object obj) =>
    {
        if (rcvBytes != null)
        {
// handle the ecvBytes here……
        }
   }));
}

有时候发现，串口接收的回来的数据是以8个字节为一次发回来的，当远程发过来的数据长度大于8，如达到11字节时，会分8字节和3字节回来。这种情况要特殊处理。

public static Byte[] ReadDeviceCOMBytes()
{
    try
    {
        List byteList = new List();
        byte[] rcvBytes = null;
        do
        {
            int count = DeviceCOM.BytesToRead;
            Console.WriteLine("in ReadDeviceCOMBytes : count={0}", count);

            rcvBytes = new byte[count];
            DeviceCOM.Read(rcvBytes, 0, count);
            foreach (byte by in rcvBytes)
            {
                byteList.Add(by);
                if (byteList.Count == 11)
                    break;
            }
        } while (byteList.Count < 11);

        return byteList.ToArray();
    }
    catch
    {
        return null;
    }
}

参考文献：

http://blog.csdn.net/chenhongwu666/article/details/40142513