a small working sample of a tool as simple as possible using webclient (and async)

getcountryforip.cs

namespace nurl1
{
	class Program
	{
		public static void Main(string[] args)
		{
			if(args.Length<1 || !(Regex.Match(args[0],@"\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b").Success))
				throw new ArgumentException("not a valid ip number");
			
			Console.WriteLine("Country for ip [{0}]",args[0]);
			
			new WebClient()
				.DownloadStringTaskAsync("http://api.hostip.info/country.php?ip=" + args[0])
				.ContinueWith((t)=>{
					Console.WriteLine(t.Result);
					Console.Write("Press any key to continue . . . ");
			});
			
			Console.WriteLine("----------------------------");
			
			Console.ReadKey(true);
		}
	}
}