使用PrincipalContext搜索Active Directory组时，不会返回某些UserPrincipal属性

Question

I am writing a C# application to display users within a user supplied security group. It seems like all my test cases work except when I search against "Domain Users". When I do neither Surname or GivenName will return values. All other groups return those values. I'm stumped.

Test 1: Domain Admins

Results: All Surname and GivenName displayed in GridView

Test 2: Domain Users

Results: No Surname or GivenName's are displayed

Note: If I change the properties to any other AD User Property, eg, Name, SAM, etc., those all display without issue.

namespace adsearch
{
    public partial class frmViewGroupMembers : Form
    {
        private string group;
        private DataTable GroupMembers = new DataTable();

        public frmViewGroupMembers()
        {
            InitializeComponent();
        }

        public void ShowGroupMembers(string groupName) {
            GroupMembers.Columns.Add("Last Name");
            GroupMembers.Columns.Add("First Name");


            using (PrincipalContext context = new PrincipalContext(ContextType.Domain, "mydomain.local")) {
                using (GroupPrincipal group = GroupPrincipal.FindByIdentity(context, groupName))
                {
                    foreach (UserPrincipal user in group.GetMembers(true).OfType<UserPrincipal>())
                    {
                        GroupMembers.Rows.Add(user.Surname, user.GivenName);
                    }                  
                }
            }

            dgvGroupMembers.DataSource = GroupMembers;
            dgvGroupMembers.Sort(dgvGroupMembers.Columns[0], ListSortDirection.Ascending);
            this.Show();
        }      
    }
}

Answer 1

Have you checked in Active Directory to confirm that the User has the required fields filled in? Often the assumption is made that filling in the "Display Name" is enough, but both the "First Name" (GivenName) and "Last Name" (SurName) need to be filled in for GivenName and SurName to be populated.

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