TFS API: List all TFS Users

The following code lists all TFS users over the API.

[System.Diagnostics.DebuggerStepThrough]
private ICredentials GetCredentials()
{
  return new NetworkCredential("user", "pwd", "domain");
}

    public TfsWrapper()
    {
      server = new TeamFoundationServer("https://your.tfs.com/tfs/store", GetCredentials());
      server.Authenticate();
      css = (ICommonStructureService)server.GetService(typeof(ICommonStructureService));
      gss = (IGroupSecurityService)server.GetService(typeof(IGroupSecurityService));
      tfsIdentities = new List<Identity>();
    }


    public void ReadTfsUsers()
    {
      TeamProject tp = this.GetTeamProject();
      Identity[] appGroups = gss.ListApplicationGroups(tp.ArtifactUri.AbsoluteUri);

      foreach (Identity group in appGroups)
      {
        Identity[] groupMembers = gss.ReadIdentities(SearchFactor.Sid, new string[] { group.Sid }, QueryMembership.Expanded);
        foreach (Identity member in groupMembers)
        {
          Console.WriteLine(member.DisplayName);
          if (member.Members != null)
          {
            foreach (string memberSid in member.Members)
            {
              Identity memberInfo = gss.ReadIdentity(SearchFactor.Sid, memberSid, QueryMembership.None);

              if (memberInfo.Type == IdentityType.WindowsUser)
              {
                if (!this.tfsIdentities.Contains(memberInfo))
                  this.tfsIdentities.Add(memberInfo);

                // Console.WriteLine(" {0}", memberInfo.DisplayName);
                //Console.WriteLine("AccountName :" + memberInfo.AccountName);
                //Console.WriteLine("Deleted :" + memberInfo.Deleted);
                //Console.WriteLine("Description :" + memberInfo.Description);
                //Console.WriteLine("DisplayName :" + memberInfo.DisplayName);
                //Console.WriteLine("DistinguishedName :" + memberInfo.DistinguishedName);
                //Console.WriteLine("Domain :" + memberInfo.Domain);
                //Console.WriteLine("MailAddress :" + memberInfo.MailAddress);
                //Console.WriteLine("Sid :" + memberInfo.Sid);
                //Console.WriteLine("Type :" + memberInfo.Type.ToString());
                //Console.WriteLine("*********************************");
              }
            }
          }
        }
      }
    }