How to get all users from TFS?

Hello!

I want to get all users from TFS. I find this blog , but it not works: some classes are obsolete.

So, i try to rewrite code like this:

 IIdentityManagementService gss=(IIdentityManagementService)_configurationServer.GetService((typeof(IIdentityManagementService)));
                String[] searchValues={"Team Foundation Valid Users"};
                TeamFoundationIdentity[][] UserId=gss.ReadIdentities(IdentitySearchFactor.AccountName,searchValues,MembershipQuery.Expanded,ReadIdentityOptions.ExtendedProperties);

                foreach(var user in UserId)
                {
                    foreach (var u in user)
                    {
                        Console.WriteLine("DisplayName: "+u.DisplayName);
                        foreach (var u1 in u.Members)
                        {
                            Console.WriteLine(u1.Identifier+" "+u1.Data);
                        }
                    }
                }

I am confused - it not works for me.

Let me publish code from that blog:

IGroupSecurityService gss = (IGroupSecurityService)server.GetService(typeof(IGroupSecurityService));
            Identity SIDS = gss.ReadIdentity(SearchFactor.AccountName, "Team Foundation Valid Users", QueryMembership.Expanded);
            Identity[] UserId = gss.ReadIdentities(SearchFactor.Sid, SIDS.Members, QueryMembership.None);
            list_users.Items.Clear();
            foreach (Identity user in UserId)
            {
                ListViewItem li = new ListViewItem(user.DisplayName);
                li.SubItems.Add(user.AccountName);
                li.SubItems.Add(user.MailAddress);
                li.SubItems.Add(user.Sid);
                list_users.Items.Add(li);
            }

This obsolete code doesnt work: 

IGroupSecurityService gss == null

So, please, tell me how to get all users from TFS?

Thank you!