System.IO.Ports.SerialPort.Dispose C# (CSharp) Method

		protected override void Dispose (bool disposing)
		{
			if (!is_open)
				return;
			
			is_open = false;
			// Do not close the base stream when the finalizer is run; the managed code can still hold a reference to it.
			if (disposing)
				stream.Close ();
			stream = null;
		}

        // private static System.IO.Ports.SerialPort serialPort1 = new System.IO.Ports.SerialPort();
        public static void display(string Line1, string Line2, string Line3, string Line4)
        {
            System.IO.Ports.SerialPort serialPort1 = new System.IO.Ports.SerialPort();
            try
            {
                serialPort1.PortName  = PortName;
                serialPort1.BaudRate  = Convert.ToInt32(BaudRate);
                serialPort1.DataBits  = Convert.ToInt32(DataBits);
                serialPort1.Parity    = Parity.None;
                serialPort1.StopBits  = StopBits.One;
                serialPort1.DtrEnable = true;
                serialPort1.RtsEnable = true;
                serialPort1.Open();
                serialPort1.Write(new byte[] { 0x0C }, 0, 1);
                // byte[] data = Encoding.ASCII.GetBytes(Line1 + space1 + Line2); // your byte data;
                serialPort1.Write(Line1 + Line2);

                //Goto Bottem Line
                //serialPort1.Write(new byte[] { 0x0A, 0x0D }, 0, 2);
                //byte[] data1 = Encoding.ASCII.GetBytes(Line3 + space2 + Line4); // your byte data;
                serialPort1.Write(Line3 + Line4);


                serialPort1.Close();
                serialPort1.Dispose();
                serialPort1 = null;
            }
            catch (Exception)
            {
                serialPort1.Close();
                serialPort1.Dispose();
                serialPort1 = null;
                //MessageBox.Show(ex.ToString() + "----"+ PortName+"----"+ BaudRate.ToString()+"----"+ DataBits.ToString());
            }
        }