private void frmInHoaDon_Load(object sender, EventArgs e)
{
ChiTietHoaDonData chitietdata = new ChiTietHoaDonData();
TT_NHOM_QLKS.Report.HoaDon hoadon = new TT_NHOM_QLKS.Report.HoaDon();
hoadon.SetDataSource(chitietdata.LaydanhSachChiTietHoaDon());
crystalReportViewer1.ReportSource = hoadon;
}