user_id, user_name, user_firstname and user_displayname. @param user_id string User ID @param user_name string User's name @param user_firstname string User's first name @param user_displayname string User's display name @return string */ public static function getUserCN($user_id, $user_name, $user_firstname, $user_displayname) { if (!empty($user_displayname)) { return $user_displayname; } if (!empty($user_name)) { if (!empty($user_firstname)) { return $user_firstname.' '.$user_name; } else { return $user_name; } } elseif (!empty($user_firstname)) { return $user_firstname; } return $user_id; } } ?>