//Delete private void buttonBkDel_Click(object sender, EventArgs e) { DialogResult ans = MessageBox.Show("Are you sure you want to delete the Book information?", "Delete Confirmation", MessageBoxButtons.YesNo, MessageBoxIcon.Information); if (ans == DialogResult.Yes) { if (OrderDA.SearchByBook(Convert.ToInt64(textBoxBkISBN.Text)) != null) { MessageBox.Show("This book has open orders in the system, please verify the orders before deleting this book.", "ALERT!"); return; } BookDA.Delete(createBook().BkISBN); BookDA.ListBooks(listViewBooks); UpdateComboBoxes(); } }