IsTldMatch Uri extension method, nothing special, really.

IsTldMatch.cs

using System;
using System.Web;

namespace Application
{
    public static class Extensions
    {
        public static bool IsTldMatch(this Uri Url, string Tld)
        {
            if (HttpRequest.Url.Host == Tld || HttpRequest.Url.Host.EndsWith(string.Concat(".", Tld)) // could just as well return the result of this...
            {
                return true;
            }
            else
            {
                return false;
            }
        }
    }
}