private void iconButtonSupply_Click(object sender, EventArgs e)
 {
     if (textBoxISBN.Text.Length == 0)
     {
         MessageBox.Show("ISBN不能为空");
         return;
     }
     if (BookDataAccess.IsBookExisted(textBoxISBN.Text))
     {
         SupplierOrderDataAccess.InsertSupplierOrderOfExistentBook(SupplierInfo.supplier.Id, DateTime.Now, (int)numericUpDownAmount.Value, textBoxISBN.Text);
         MessageBox.Show("发货成功");
     }
     else
     {
         MessageBox.Show("您供应的图书ISBN在书库中未被检索到,\r\n您需要录入关于新书的信息");
         NewBookForm newBookForm = new NewBookForm();
         SendOrderInfoEvent += newBookForm.GetInfo;
         SendOrderInfoEvent.Invoke(textBoxISBN.Text, (int)numericUpDownAmount.Value);
         newBookForm.ShowDialog();
     }
 }