Getting a list of groups membership (memberOf) in Active Directory [duplicate]

Question

I'am back with my Active Directory tool...

I'am trying to list the groups in the "member of" attribute of a user. Below is the function I use:

public static DataTable ListGroupsByUser(string selectedOu)
{
    DataTable groupListByUser = new DataTable();
    String dom = "OU=" + selectedOu + ",OU=XXX,DC=XXX,DCXXX,DC=XXX,DC=XXX";
    DirectoryEntry directoryObject = new DirectoryEntry("LDAP://" + dom);

    DataColumn column;
    DataRow row;

    column = new DataColumn();
    column.ColumnName = "ID";
    groupListByUser.Columns.Add(column);

    column = new DataColumn();
    column.ColumnName = "User";
    groupListByUser.Columns.Add(column);

    column = new DataColumn();
    column.ColumnName = "Groups";
    groupListByUser.Columns.Add(column);
    int i = 1;

    foreach (DirectoryEntry child in directoryObject.Children)
    {                
        row = groupListByUser.NewRow();
        groupListByUser.Rows.Add(row);
        row["ID"] = i++;

        if (child.Properties["memberOf"].Value != null)
        {                    
            row["User"] = child.Properties["sAMAccountName"].Value.ToString();
            row["Groups"] = child.Properties["memberOf"].Value.ToString();
        }
        else
        {
            row["Groups"] = "blabla";
        }
    }
    return groupListByUser;
}

It returns the right group for users belonging to only one group. As soon as There's more than one group, it returns System.Object[].

How can I do to see all groups ?

Answer 1

The problem is your Properties["memberOf"].Value.ToString().

I made a little investigation and this code worked for me:

var memberGroups = child.Properties["memberOf"].Value;

if (memberGroups.GetType() == typeof(string))
{
    row["Groups"] = (String)memberGroups;
}
else if (memberGroups.GetType().IsArray)
{
    var memberGroupsEnumerable = memberGroups as IEnumerable;

    if (memberGroupsEnumerable != null)
    {
        var asStringEnumerable = memberGroupsEnumerable.OfType<object>().Select(obj => obj.ToString());
        row["Groups"] = String.Join(", ", asStringEnumerable);
    }
}
else
{
    row["Groups"] = "No group found.";
}

It's not very cute but it works and gives room for further improvements. ;-)

Answer 2

If you're on .NET 3.5 and up, you should check out the System.DirectoryServices.AccountManagement (S.DS.AM) namespace. Read all about it here:

• Managing Directory Security Principals in the .NET Framework 3.5
• MSDN docs on System.DirectoryServices.AccountManagement

Basically, you can define a domain context and easily find users and/or groups in AD:

// set up domain context
PrincipalContext ctx = new PrincipalContext(ContextType.Domain);

// find a user
UserPrincipal user = UserPrincipal.FindByIdentity(ctx, "SomeUserName");

if(user != null)
{
   var groups = user.GetGroups();
   // or there's also:
   //var authGroups = userByEmail.GetAuthorizationGroups()
}

The calls to GetGroups() or GetAuthorizationGroups() will return nested group membership, too - so no need for you to hunt those nested memberships anymore!

The new S.DS.AM makes it really easy to play around with users and groups in AD!