asp.net获取顶级域名

using System;
using System.Net;

public class TopLevelDomainHelper
{
    public static string GetTopLevelDomain(string url)
    {
        try
        {
            Uri uri = new Uri(url);
            string host = uri.Host;
            string[] parts = host.Split('.');
            string topLevelDomain = parts[parts.Length - 1];
            if (parts.Length > 2 && parts[parts.Length - 2].Length < 4)
            {
                topLevelDomain = parts[parts.Length - 2] + "." + parts[parts.Length - 1];
            }
            return topLevelDomain;
        }
        catch (Exception ex)
        {
            Console.WriteLine("Error: " + ex.Message);
            return null;
        }
    }
}

// 示例使用
string url = "https://www.example.com/path";
string topLevelDomain = TopLevelDomainHelper.GetTopLevelDomain(url);
Console.WriteLine("Top Level Domain: " + topLevelDomain);