System.DirectoryServices很慢？

Question

当用户登录网站时,我正在使用以下代码在Active Directory中查找信息.对本地域运行它非常快,但是通过VPN运行到远程可信域,它非常慢(需要大约7或8秒).将dsa.msc从同一个盒子运行到远程域几乎和在本地运行它一样快.

我正在使用属性过滤来检索可能的最小数据量,因此在这种情况下System.DirectoryServices是否存在某些内在缓慢的问题,或者是否有人对如何提高性能有任何提示？

通过VPN的网络连接很好,只有这个代码运行缓慢.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.DirectoryServices;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            using (var LDAPConnection = new DirectoryEntry("LDAP://domain/dc=domain,dc=com", "username", "password"))
            {
                LDAPConnection.AuthenticationType = AuthenticationTypes.Secure;
                using (DirectorySearcher Searcher = new DirectorySearcher(LDAPConnection))
                {
                    Searcher.Filter = "(&(&(objectclass=user)(objectcategory=person))sAMAccountName=username)";
                    Searcher.PropertiesToLoad.Add("mail");

                    SearchResult result = Searcher.FindOne(); //this line takes ages!

                    string EmailAddress = result.Properties["mail"][0].ToString();
                    Console.WriteLine(EmailAddress);
                }
            }
        }
    }
}

Answer 1

另一个建议是System.DirectoryServices.Protocols直接使用; 你的代码看起来像:

string filter = "(&(&(objectclass=user)(objectcategory=person))" + 
                "sAMAccountName=username)";
NetworkCredential credentials = new NetworkCredential(...);
LdapDirectoryIdentifier directoryIdentifier = 
   new LdapDirectoryIdentifier("server", 389, false, false);
using (LdapConnection connection = 
   new LdapConnection(directoryIdentifier, credentials, AuthType.Basic))
{
    connection.Timeout = new TimeSpan(0, 0, 30);
    connection.SessionOptions.ProtocolVersion = 3;
    SearchRequest search = 
        new SearchRequest(query, filter, SearchScope.Base, "mail");
    SearchResponse response = connection.SendRequest(search) as SearchResponse;
    foreach(SearchResultEntry entry in response.Entries)
    {
        Console.WriteLine(entry.Attributes["mail"][0]);
    }
}