C# / DirectoryEntry / All Groups / Filtering

Question

I'm messing up with getting a full and usable list of all recursive groups to populate up a dropdownlist control to select a group to administer right within a ASP.net page.

The used Code:

List<string> groups = new List<string>();

using (DirectorySearcher searcher = new DirectorySearcher(dEntry))
{
    searcher.Filter = "(objectCategory=group)";
    foreach (SearchResult result in searcher.FindAll())
    {
        string group = result.Path.Substring(result.Path.IndexOf("/CN=")+4);
        string formatedResult = group.Substring(0, group.IndexOf(",CN="));
        groups.Results.Add(formatedResult);
    }
}

The result list is long, containing a bunch of system-groups, which are not needed. Only specific system-groups should be included in the groups list, like "Administrators" and all "non-system-defined" or "system-related" groups. (Like: Departments, Applicationgroups, etc. defined in the AD-Structure).

Any hint how to do that with DirectoryEntry?

Answer 1

If the 0x1 flag is present in groupType attribute, the group is created by the system. Can modify the filter to search for:

system groups:

(&(objectCategory=group)(groupType:1.2.840.113556.1.4.803:=1))

non-system groups:

(&(objectCategory=group)(!(groupType:1.2.840.113556.1.4.803:=1)))