private void btnThanhToan_Click(object sender, EventArgs e) { try { if (hd.KTraTonTai(txtMaHD.Text) == false) { for (int i = 0; i < dgvCTHD.Rows.Count - 1; i++) { string mahh = dgvCTHD.Rows[i].Cells[0].Value.ToString(); string soluong = dgvCTHD.Rows[i].Cells[2].Value.ToString(); string dongia = dgvCTHD.Rows[i].Cells[3].Value.ToString(); hd.ThemHHVaoHoaDon(txtMaHD.Text, mahh, int.Parse(soluong), float.Parse(dongia)); hh.CapNhatSoLuongTonHH(mahh, int.Parse(soluong)); } float tongtien = 0; for (int i = 0; i < dgvCTHD.Rows.Count - 1; i++) { tongtien += float.Parse(dgvCTHD.Rows[i].Cells[3].Value.ToString()); } hd.CapNhatHD(txtMaHD.Text, tongtien); MessageBox.Show("Thanh toán thành công"); InHD(); for (int i = 0; i < dgvCTHD.Rows.Count - 1; i = 0) { dgvCTHD.Rows.RemoveAt(i); } btnThanhToan.Enabled = false; block(); ClearDL(); dgvMH.DataSource = hh.getDSHangHoa(); } } catch { MessageBox.Show("Lỗi!!"); } }