public static string GetDomain(string s)
{
string host = s;
string[] arr = host.Split('.');
if (arr.Length < 3 || RegExp.IsIP(host))
{
return(host);
}
string domain = host.Remove(0, host.IndexOf(".") + 1);
if (domain.StartsWith("com.") || domain.StartsWith("net.") || domain.StartsWith("org.") || domain.StartsWith("gov."))
{
return(host);
}
return(domain);
}