#region 串口打印
        //打印函数，参数为打印机的命令或者其他文本！
        public bool COMWrite(string portName, int baudRate, Parity parity, int dataBits, StopBits stopBits, string myString)
        {
            try
            {
                SerialPort ComPort = new SerialPort(portName, baudRate, parity, dataBits, stopBits);
                if (ComPort.IsOpen)
                {
                    ComPort.Close();
                }
                ComPort.Open();
                ComPort.WriteLine(myString);
                ComPort.Close();
                return true;
            }
            catch (Exception ex)
            {
                return false;
            }
        }
        #endregion 并口打印


        #region 并口打印

        [StructLayout(LayoutKind.Sequential)]
        private struct OVERLAPPED
        {
            int Internal;
            int InternalHigh;
            int Offset;
            int OffSetHigh;
            int hEvent;
        }
        [DllImport("kernel32.dll")]
        private static extern int CreateFile(string lpFileName, uint dwDesiredAccess, int dwShareMode, int lpSecurityAttributes, int dwCreationDisposition, int dwFlagsAndAttributes, int hTemplateFile);

        [DllImport("kernel32.dll")]
        private static extern bool WriteFile(int hFile, byte[] lpBuffer, int nNumberOfBytesToWriter, out int lpNumberOfBytesWriten, out OVERLAPPED lpOverLapped);

        [DllImport("kernel32.dll")]
        private static extern bool CloseHandle(int hObject);

        private int iHandle;

        //打开LPT 端口
        public bool LPTOpen()
        {
            iHandle = CreateFile("lpt1", 0x40000000, 0, 0, 3, 0, 0);
            if (iHandle != -1)
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        //打印函数，参数为打印机的命令或者其他文本！
        public bool LPTWrite(string myString)
        {
            if (!LPTOpen()) { return false; }
            if (iHandle != 1)
            {
                int i;
                OVERLAPPED x;
                byte[] mybyte = System.Text.Encoding.Default.GetBytes(myString);
                //return WriteFile(iHandle, mybyte, mybyte.Length, out i, out x);
                if (WriteFile(iHandle, mybyte, mybyte.Length, out i, out x))
                {
                    LPTClose();
                    return true;
                }
                else
                {
                    return false;
                }

            }
            else
            {
                throw new Exception("端口未打开~！");
                return false;
            }
        }
        //关闭打印端口
        public bool LPTClose()
        {
            return CloseHandle(iHandle);
        }
        #endregion 并口打印