private void Btndel_Click(object sender, EventArgs e) { Activity_DAO activity_dao = new Activity_DAO(); int activityDelId = 0; for (int i = 0; i < activityListView.Items.Count; i++) { if (activityListView.Items[i].Checked) { activityDelId = int.Parse(activityListView.Items[i].Text); } } activity_dao.delActivityById(activityDelId); refreshActivities(); }