// initializers
        protected void Page_Load(object sender, EventArgs e)
        {
            NinaSubscriptionsMaster master = this.Master as NinaSubscriptionsMaster;
            master.setHeaderTitle(settingsHelper.get("title_bekijk_inschrijvingen"));

            userProfile user = master.getLoggedInUserProfile();
            if (user == null || user.isAdmin == false) { Response.Redirect("~/Pages/Public/bekijkAanbod.aspx"); };

            if (!IsPostBack) {
                crud crud = new crud();

                // fill course dropdown
                List<course> allCourses = crud.getAllCourses();
                course emptyCourse = new course() { id = 0 };
                allCourses.Insert(0, emptyCourse);
                ddCourseNames.DataSource = allCourses;
                ddCourseNames.DataTextField = "name";
                ddCourseNames.DataValueField = "id";
                ddCourseNames.DataBind();

                List<userProfile> allUserProfiles = crud.getAllUserProfiles();
                userProfile emptyProfile = new userProfile() { id = 0 };
                allUserProfiles.Insert(0, emptyProfile);
                ddUserProfiles.DataSource = allUserProfiles;
                ddUserProfiles.DataTextField = "fullname";
                ddUserProfiles.DataValueField = "id";
                ddUserProfiles.DataBind();

                cldrDates.SelectedDate = DateTime.Now;
            }
        }