private void BindDropDown() { if (!string.IsNullOrWhiteSpace(GetAttributeValue("GroupTypes"))) { var groupTypeService = new GroupTypeService(new RockContext()); List <String> groupTypeGuids = GetAttributeValue("GroupTypes").Split(',').ToList(); List <int> groupTypeIds = groupTypeService.GetListByGuids(groupTypeGuids.Select(Guid.Parse).ToList()).Select(gt => gt.Id).ToList(); gpGroups.IncludedGroupTypeIds = groupTypeIds; } }