Find the IPAddress to Location

IpAddressToLocation.cs

using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Linq.Expressions;
using System.Net;
using System.Text;
using System.Threading.Tasks;

namespace IpAddressAccess
{
    public class IPAddressLocation
    {
        public string ip { get; set; }
        public string country_code { get; set; }
        public string country_name { get; set; }
        public string region_code { get; set; }
        public string region_name { get; set; }
        public string city { get; set; }
        public string zip_code { get; set; }
        public string time_zone { get; set; }
        public float latitude { get; set; }
        public float longitude { get; set; }
        public int metro_code { get; set; }
    }

    class Program
    {
        private static string _defaultCookieValue = "NCUTY";

        static void Main(string[] args)
        {
            foreach (var ip in GetIPAddress())
            {
                var output = _GetCountryCodeFromIP(ip);
                Console.WriteLine("IpAddress {0}, Country Code: {1}", ip, output);
            }
            Console.ReadLine();
        }

        private static string _GetCountryCodeFromIP(string ipaddress)
        {
            try
            {
                string url = "http://freegeoip.net/json/" + ipaddress;
                WebClient client = new WebClient();
                string jsonstring = client.DownloadString(url);
                var results = JsonConvert.DeserializeObject<IPAddressLocation>(jsonstring);
                return String.IsNullOrEmpty(results.country_code) ? _defaultCookieValue : results.country_code;
            }
            catch (WebException ex)
            {
                return _defaultCookieValue;
            }
        }

        public static IEnumerable<string> GetIPAddress()
        {
            using (StreamReader readFile = new StreamReader("./IPAddress.csv"))
            {
                string line;
                string[] row;
                while ((line = readFile.ReadLine()) != null)
                {
                    row = line.Split(',');
                    yield  return row[0];
                }
            }
        }
    }

}