sms sending application

public static Int16 Comm_Port = 0;
       public static Int32 Comm_BaudRate = 0;
       public static Int32 Comm_TimeOut = 0;
       public static GsmCommMain comm;
   }

private void button1_Click(object sender, EventArgs e)
        {
            GsmCommMain comm = new GsmCommMain("COM4", 19200, 300);

            try
            {
                comm.Open();

                string CELL_Number, SMS_Message;

                SmsSubmitPdu pdu1;
            
                if (comm.IsConnected() == true)
                {
                    if (number.Text.ToString() == "")
                    {
                        MessageBox.Show("Kindly Add Cell Number\r\n\nFor Example\n\n+9231234567", "Information", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                        return;
                    }
                    else if (message.Text.ToString() == "")
                    {
                        MessageBox.Show("Kindly Add Your Message Text", "Information", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                        return;
                    }

                    CELL_Number = number.Text.ToString();
                    SMS_Message = message.Text.ToString();

                    MessageBox.Show("Kindly Re-Check Your SMS & CELL NUMBER \r\n\nCELL # : " + CELL_Number + "\r\n\nMESSAGE TEXT : " + SMS_Message, "SMS INFO", MessageBoxButtons.OKCancel, MessageBoxIcon.Information);

                        Cursor.Current = Cursors.WaitCursor;

                        pdu1 = new SmsSubmitPdu(SMS_Message, CELL_Number, "");

                        comm.SendMessage(pdu1);

                        Cursor.Current = Cursors.Default;

                        MessageBox.Show("M E S S A G E - S E N T", "Information", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        comm.Close();
                }
            }

                    catch (Exception )
                    {
                        MessageBox.Show("Error Sending SMS To Destination Address\r\n\n Connection Has Been Terminated !!!\r\n\n", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                        
                    }
                }
            }
           
        }