private void button3_Click(object sender, EventArgs e) { BorrowBL a = new BorrowBL(); BorrowDA b = new BorrowDA(); DateTime brDate = new DateTime(); try { brDate = DateTime.ParseExact(textBox4.Text, "d/M/yyyy", null); } catch (Exception ex) { MessageBox.Show(ex.Message); return; } DateTime dueDate = brDate.AddDays(14); textBox5.Text = dueDate.ToShortDateString(); int copyNum = int.Parse(textBox3.Text); int brNum = int.Parse(textBox1.Text); CirculatedCopy h = new CirculatedCopy(); a.SetIdMax(); h.Id = ++a.idMax; h.CopyNumber = copyNum; h.BorrowerNumber = brNum; h.BorrowedDate = brDate; h.DueDate = dueDate; b.insertBorrow(h); b.borrowUpdate(copyNum); DataSet ds = b.SelectDS(brNum); DataView dv = new DataView(ds.Tables[0]); dataGridView1.DataSource = dv; bool test2 = a.checkReserve1(copyNum); bool test3 = a.checkReserve(copyNum, b.getBoNum(copyNum), int.Parse(textBox1.Text)); if (test2 && test3) { b.borrowReUpdate(b.getBoNum(copyNum), int.Parse(textBox1.Text)); } button3.Enabled = false; }