private void LoadData() { string id = (Category.SelectedValue != string.Empty ? Category.SelectedValue : "23"); Document document = new Document(Convert.ToInt32(UmbracoCustom.GetParameterValue(UmbracoType.GymnastNode))); Property property = document.getProperty("exercise"); var exercises = UmbracoCustom.GetDataTypeGrid(property).Where(g => g.category == id); Exercise.Items.Clear(); foreach (var exercise in exercises) { Exercise.Items.Add(new ListItem(exercise.exercise, exercise.id)); } }