private void lstBooks_SelectedIndexChanged(object sender, EventArgs e)
{
using (BorrowService service = new BorrowService())
{
if (lstBooks.SelectedItem == null)
{
return;
}
int bookId = (lstBooks.SelectedItem as BookDTO).BookId;
lblAlınmaAdedi.Text = service.GetNumberOfBorrows(bookId) + " Adet";
}
}