从Active Directory结果中删除组仅返回用户

Question

我正在使用Active Directory在自动填充输入字段中返回用户列表。当用户键入组的名称时，我遇到的问题是它返回数据。理想情况下，我想要的只是显示用户，而不是组。这可能吗？非常感谢你的帮助。提前谢谢。

    public List<Client> Search(string name)
    {
        List<Client> results = new List<Client>();
        string domainname = "domain";

        string rootQuery = "LDAP://domain.com/DC=domain,DC=com";
        name = name + "*";

        using (DirectoryEntry root = new DirectoryEntry(rootQuery))
        {
            domainname = root.Properties["Name"].Value.ToString();

            using (DirectorySearcher searcher = new DirectorySearcher(root))
            {
                //searcher.Filter = "(ObjectClass=" + name + ")"; //searchFilter;
                searcher.Filter = "(SAMAccountName=" + name + ")"; //searchFilter;
                searcher.PropertiesToLoad.Add("displayName");
                searcher.PropertiesToLoad.Add("sAMAccountName");
                searcher.PropertiesToLoad.Add("mail");

                SearchResultCollection src = searcher.FindAll();
                foreach (SearchResult sr in src)
                {
                    Client r = new Client();
                    r.domain = domainname;

                    // Iterate through each property name in each SearchResult.
                    foreach (string propertyKey in sr.Properties.PropertyNames)
                    {
                        ResultPropertyValueCollection valueCollection = sr.Properties[propertyKey];

                        if (propertyKey == "mail")
                        {
                            foreach (Object propertyValue in valueCollection)
                            {
                                r.email = propertyValue.ToString();
                            }
                        }
                        if (propertyKey == "displayname")
                        {
                            foreach (Object propertyValue in valueCollection)
                            {
                                r.name = propertyValue.ToString();
                            }
                        }
                        if (propertyKey == "samaccountname")
                        {
                            foreach (Object propertyValue in valueCollection)
                            {
                                r.loginName = propertyValue.ToString();
                            }
                        }

                    }
                    if (r.name != null && r.email != null)
                    {
                        results.Add(r);
                    }

                }
            }
        }
        return results;
    }