private void AddCopies_Button_Click(object sender, EventArgs e)
{
Book book = lbBooks.SelectedItem as Book;
string copies = AddCopies_textBox.Text;
int number;
bool isNumber = int.TryParse(copies, out number);
if (isNumber == true)
{
bookCopyService.AddCopies(book, number);
MessageBox.Show("Copies added:" + number);
}
else
{
MessageBox.Show("Input must be a number");
}
}
