IP Address Lookup in Bulk Using C-Sharp and MySQL Database

/// <summary>
/// IP Address (ipv6) Lookup in Bulk Using C# and MySQL Database
/// Free geolocation database can be downloaded at:
/// http://lite.ip2location.com/
/// </summary>

void DisplayFileContents(HttpPostedFile file)
   {
       Stream theStream = FileUpload1.PostedFile.InputStream;
       StringBuilder display = new StringBuilder();
       using (StreamReader sr = new StreamReader(theStream))
       {
           string line;
           char[] delimiter1 = new char[] { ',' };

           while ((line = sr.ReadLine()) != null)
           {
               string[] iplist = line.Split(delimiter1, StringSplitOptions.None);

               foreach (string IP in iplist)
               {
                   display.Append("IP Address : " + IP.ToString() + "\n");

                   string ip_addr = IP;

                   System.Numerics.BigInteger ip_num = ip_to_number(ip_addr);
                   String ip_no = ip_num.ToString();
                   string query = "SELECT country_code, country_name , city_name , region_name, latitude,longitude,zip_code,time_zone FROM ip2location_db11 WHERE ip_to >= " + ip_no + " order by ip_to limit 1";
                   string[] data = Get_Data(query);

                   string country_code = data[0];
                   string country_name = data[1];
                   string city_name = data[2];
                   string region_name = data[3];
                   string latitude = data[4];
                   string longitude = data[5];
                   string zip_code = data[6];
                   string time_zone = data[7];

                   //Define the result file that you want to output
                   string filePath = Server.MapPath("~") + "result.csv";

                   using (StreamWriter Sw = File.AppendText(filePath))
                   {
                       string output = string.Format("\"" + IP + "\"" + "," + "\"" + country_code + "\"" + "," + "\"" + country_name + "\"" + "," + "\"" + city_name + "\"" + "," + "\"" + region_name + "\"" + "," + "\"" + latitude + "\"" + "," + "\"" + longitude + "\"" + "," + "\"" + zip_code + "\"" + "," + "\"" + time_zone + "\"");

                       Console.WriteLine(output);
                       Sw.WriteLine(output);

                   }
                   Label3.Text = "Result File Path : " + Path.GetFullPath(filePath) + "<br>";
               }
           }
       }

       Label4.Text = "Please DELETE the result file if you want to upload a new file! <br>";

   }