如何以编程方式找出Windows中的域控制器是哪台计算机？

using System;
using System.DirectoryServices;

public class DomainControllerFinder
{
    public static void Main()
    {
        string domainName = "example.com";
        string domainController = FindDomainController(domainName);
        Console.WriteLine("Domain controller for {0} is {1}", domainName, domainController);
    }

    public static string FindDomainController(string domainName)
    {
        string ldapPath = string.Format("LDAP://{0}", domainName);
        using (DirectoryEntry de = new DirectoryEntry(ldapPath))
        {
            string domainController = de.Properties["dc"].Value.ToString();
            return domainController;
        }
    }
}

using System;
using System.Net;

public class DomainControllerFinder
{
    public static void Main()
    {
        string domainName = "example.com";
        string domainController = FindDomainController(domainName);
        Console.WriteLine("Domain controller for {0} is {1}", domainName, domainController);
    }

    public static string FindDomainController(string domainName)
    {
        string domainController = string.Format("_ldap._tcp.dc._msdcs.{0}", domainName);
        IPHostEntry hostEntry = Dns.GetHostEntry(domainController);
        return hostEntry.HostName;
    }
}