private void deleteBookButton_Click(object sender, EventArgs e)//删除书籍
{
Book book = bookBindingSource.Current as Book;
if (book == null)
{
MessageBox.Show("请选择一本书进行操作！");
return;
}
BookShelfService.RemoveBooks(book.BookId);
shelfBindingSource.DataSource = BookShelfService.GetAllShelfs();
}