private void Delete_btn_Click(object sender, EventArgs e) { int transaction_id = 0; try { transaction_id = (int)((Transaction)Transactions_listView.SelectedItems[0].Tag).TransactionID; } catch { ErrorMessenger.Warning("A transaction must be selected from the list"); return; } DB_API.DeleteTransaction(transaction_id); // populate transactions listBox PopulateTransactionsListView(); }