串口通信，数据会被分多次收到的处理方法

1、串口接收数据部分

    private void Sp1_DataReceived(object sender, SerialDataReceivedEventArgs e)
        {            
            Byte[] receivedData = new Byte[sp1.BytesToRead];
            sp1.Read(receivedData,0, receivedData.Length);

            lock (obj)
            {
                receiveBuf.AddRange(receivedData);
            }
        }

2、线程中处理接收到的数据

    ThreadPool.QueueUserWorkItem(ProData);

全局变量：List<byte> receiveBuf = new List<byte>();
private void ProData(object state)
        {
            List<byte> tmp = new List<byte>();
            byte[] _HeaderBuffer = new byte[8];
            while (IsOpen)
            {

                if (receiveBuf.Count > 8)
                {
                    receiveBuf.CopyTo(0, _HeaderBuffer, 0, 8);
                      //根据协议取出总包长
                    var ilen = RcsMessage.CheckData(_HeaderBuffer);
                      //如果已经接收到的数据大于一个完整的数据，从ReceiveBuf截取这部分数据工处理，
                    if (receiveBuf.Count >= ilen&&ilen>10 )
                    {
                        byte[] receivedata = new byte[ilen];
                        receiveBuf.CopyTo(0, receivedata, 0, ilen);
                        var str = RcsMessage.ReadData(receivedata);
                        AddContent(str);
                        receiveBuf.RemoveRange(0, ilen);
                    }
                   
                } 
                Thread.Sleep(100);
            }
        
        
        }