我是否可以仅使用extensionAttribute1创建DirectorySearcher过滤器？

Question

我有一个使用DirectorySearcher的类，它根据以下可选过滤器返回结果：

的samAccountName 给定的名称 SN

但是，我需要创建一个directorysearcher，它从基于AD的soley返回一个用户条目，其值为“extensionAttribute1”。

是否可以使用extensionAttribute1创建仅针对用户帐户搜索AD的过滤器？

这是当前的代码：

    public static DataTable tblUserSearchResults(string searchstring, string searchproperty)
    {
        using (DirectoryEntry de = new DirectoryEntry(ConfigurationManager.ConnectionStrings["ADConnectionString"].ToString()))
        {
            //create instance of the directory searcher
            using (DirectorySearcher deSearch = new DirectorySearcher())
            {
                //set the search filter
                deSearch.SearchRoot = de;
                deSearch.SearchScope = SearchScope.Subtree;
                switch (searchproperty)
                {
                    case "un":
                        deSearch.Filter = "(&(objectCategory=person)(objectClass=user)(!userAccountControl:1.2.840.113556.1.4.803:=2)(mail=*)(samAccountName=" + searchstring.Trim() + "*))";
                        break;
                    case "fn":
                        deSearch.Filter = "(&(objectCategory=person)(objectClass=user)(!userAccountControl:1.2.840.113556.1.4.803:=2)(mail=*)(givenname=" + searchstring.Trim() + "*))";
                        break;
                    case "ln":
                        deSearch.Filter = "(&(objectCategory=person)(objectClass=user)(!userAccountControl:1.2.840.113556.1.4.803:=2)(mail=*)(sn=" + searchstring.Trim() + "*))";
                        break;
                    default:
                        deSearch.Filter = "(&(objectCategory=person)(objectClass=user)(!userAccountControl:1.2.840.113556.1.4.803:=2)(mail=*)(sn=" + searchstring.Trim() + "*))";
                        break;
                }

                //get the search results
                using (SearchResultCollection results = deSearch.FindAll())
                {
                    //Create a new table object
                    using (DataTable tblResults = new DataTable())
                    {
                        tblResults.Columns.Add("UserID");
                        tblResults.Columns.Add("FirstName");
                        tblResults.Columns.Add("LastName");
                        tblResults.Columns.Add("Department");
                        foreach (SearchResult result in results)
                        {
                            using (DirectoryEntry de2 = result.GetDirectoryEntry())
                            {
                                if (de2.Properties["samAccountName"].Value != null)
                                {
                                    DataRow dr = tblResults.NewRow();
                                    dr["UserID"] = de2.Properties["samAccountName"].Value.ToString();
                                    dr["FirstName"] = de2.Properties["givenname"].Value.ToString();
                                    dr["LastName"] = de2.Properties["sn"].Value.ToString();
                                    if (de2.Properties["department"].Value != null)
                                    {
                                        dr["Department"] = de2.Properties["department"].Value.ToString();
                                    }
                                    tblResults.Rows.Add(dr);
                                }
                            }
                        }
                        tblResults.DefaultView.Sort = "LastName asc, FirstName asc";
                        return tblResults;
                    }
                }
            }
        }
    }