public async Task <IActionResult> OnGetAsync() { if (Input.AccessLevelId != null) { // ویرایش var RolesList = await _RoleApplication.ListOfRolesByAccessLevelIdAsync(Input.AccessLevelId); if (RolesList == null) { throw new Exception("RolesList is null."); } ViewData["SelectedRoles"] = RolesList; return(Page()); } else { return(Page()); } }