public string GetIPByDomain(string url)
        {
            if (url.Trim() == string.Empty)
                return "";
            try
            {
                System.Net.IPHostEntry host = System.Net.Dns.GetHostEntry(url);
                return host.AddressList.GetValue(0).ToString();
            }
            catch (Exception e)
            { 
                throw e;
            }
       }