获取受信任域中的用户列表

Question

如何从受信任的域中获取用户列表？

我试图运行LDAP查询，但我无法从受信任的域获取用户。这是我的代码：

public virtual List<UserModel> SearchUsers(string textValue)
{
    var users = new List<UserModel>();
    string context;
    const string nameProperty = "name";
    const string samAccountNameProperty = "samaccountname";
    const string distinguishedNameProperty = "distinguishedname";

    if (textValue.Contains("(").Equals(true) || textValue.Contains(")").Equals(true) || textValue.Contains("*").Equals(true))
    {
        textValue = EscapeInvalidCharacters(textValue);
    }

    var filterForDomainUser ="(&(objectClass=user)(!(userAccountControl:1.2.840.113556.1.4.803:=2))(|(samaccountname=" + textValue + "*)(name=" + textValue + "*)))";

    using (HostingEnvironment.Impersonate())
    {
        using (var root = new DirectoryEntry("LDAP://RootDSE"))
        {
            context = root.Properties["defaultNamingContext"].Value.ToString();
        }

        using (var entry = new DirectoryEntry("GC://" + context))
        {
            using (
            var search = new DirectorySearcher(entry,filterForDomainUser,
                                                new[]
                                                    {
                                                        samAccountNameProperty, nameProperty,
                                                        distinguishedNameProperty
                                                    }, SearchScope.Subtree))
            {
                search.ReferralChasing = ReferralChasingOption.All;
                search.PageSize = 10;

                var resultCol = search.FindAll();

                for (var counter = 0; counter < resultCol.Count; counter++)
                {
                    var result = resultCol[counter];
                    var distinguishedName = (String)result.Properties[distinguishedNameProperty][0];
                    var domainName =
                        distinguishedName.Substring(distinguishedName.IndexOf("DC=",
                                                                                StringComparison
                                                                                    .InvariantCultureIgnoreCase))
                            .Split(',')[0].Replace("DC=", "");
                    var name = (String)result.Properties[nameProperty][0];
                    var samAccountName = string.Format("{0}{1}{2}", domainName, @"\",
                                                        result.Properties[samAccountNameProperty][0]);

                    var userModel = new UserModel
                    {
                        DisplayName = name,
                        UserName = samAccountName
                    };
                    users.Add(userModel);
                }
            }
        }
    }

    //SearchLocalUser(textValue, users);

    return users;
}