private void cbbMa_KH_SelectedValueChanged(object sender, EventArgs e)
        {
            try
            {
                dtDonDatBan.Clear();
                dtTTKhachHang.Clear();
                dtTTDonDatBan.Clear();
                dtTTHDMonAn.Clear();
                dtTTHDDV.Clear();
                tbTongTienPhaiTra.Clear();


                bllLapDonDatBan.docDanhSachDonDatBanTheoMa_KH(dtDonDatBan, cbbMa_KH.Text);
                bllKhachHang.docDanhSachKhachHangTheoMa_KH(dtTTKhachHang, cbbMa_KH.Text);
                bllLapDonDatBan.docDanhSachHoaDonMonAnTheoMa_HDMA(dtTTHDMonAn, tbMa_HDMA.Text);
                bllLapDonDatBan.docDanhSachHoaDonDichVuTheoMa_HDDV(dtTTHDDV, tbMa_HDDV.Text);

                dgvThongTin_KH.DataSource  = dtTTKhachHang;
                dgvThongTin_DDB.DataSource = dtDonDatBan;
                dgvThongTin_MA.DataSource  = dtTTHDMonAn;
                dgvThongTin_DV.DataSource  = dtTTHDDV;

                tbMa_DDB.DataBindings.Add(new Binding("Text", dtDonDatBan, "MA_DDB", true));
                tbMa_HDMA.DataBindings.Add(new Binding("Text", dtDonDatBan, "MA_HDMA", true));
                tbMa_HDDV.DataBindings.Add(new Binding("Text", dtDonDatBan, "MA_HDDV", true));
                tbTienDatBan.DataBindings.Add(new Binding("Text", dtDonDatBan, "GIABAN", true));
                tbTienDatCoc.DataBindings.Add(new Binding("Text", dtDonDatBan, "TIENDATCOC", true));
                tbTien_MA.DataBindings.Add(new Binding("Text", dtTTHDMonAn, "TRIGIA", true));
                tbTien_DV.DataBindings.Add(new Binding("Text", dtTTHDDV, "GIATRI", true));
                dtpNgayDatBan.DataBindings.Add(new Binding("Text", dtDonDatBan, "NGAYDATBAN", true));
            }
            catch (Exception)
            { }
        }