Credit Card Fraud Prevention Using .NET Framework in C#

Using IP2Location;
private void Query(string strIPAddress, string billingCountry)
{
  IPResult oIPResult = new IP2Location.IPResult();
  try
  {
    if (strIPAddress != "")
     {
      IP2Location.Component.IPDatabasePath = "C:\\Program Files\\IP2Location\\Database\\IP-COUNTRY.SAMPLE.BIN";
      oIPResult = IP2Location.Component.IPQuery(strIPAddress);
       switch(oIPResult.Status.ToString())
        {
          case "OK":
            if (oIPResult.CountryShort == billingCountry) {
              // buyer is from the same country by IP address
              } else {
              // buyer is from the different country by IP address
              }
          break;
           case "EMPTY_IP_ADDRESS":
                Response.Write("IP Address cannot be blank.");
                break;
           case "INVALID_IP_ADDRESS":
                Response.Write("Invalid IP Address.");
                break;
           case "MISSING_FILE":
                Response.Write("Invalid Database Path.");
                break;
           }
       }
       else
       {
        Response.Write("IP Address cannot be blank.");
       }
   }
    catch(Exception ex)
     {
      Response.Write(ex.Message);
     }
    finally
     {
      oIPResult = null;
     }
}