public static LinkedList <SanPham> getAllSanPham()
        {
            LinkedList <SanPham> list  = new LinkedList <SanPham>();
            DataTable            datas = SanPham_DB.getAllDataSanPham();

            for (int i = 0; i < datas.Rows.Count; i++)
            {
                string   MaSP         = datas.Rows[i].ItemArray[0].ToString();
                string   TenSP        = datas.Rows[i].ItemArray[1].ToString();
                int      SoLuong      = Convert.ToInt32(datas.Rows[i].ItemArray[2].ToString());
                DateTime NgayNhap     = Convert.ToDateTime(datas.Rows[i].ItemArray[3].ToString());
                double   GiaNhap      = Convert.ToDouble(datas.Rows[i].ItemArray[4].ToString());
                double   GiaBan       = Convert.ToDouble(datas.Rows[i].ItemArray[5].ToString());
                double   GiamGia      = Convert.ToDouble(datas.Rows[i].ItemArray[6].ToString());
                int      SoLuongBanRa = Convert.ToInt32(datas.Rows[i].ItemArray[7].ToString());
                string   LoaiSP       = datas.Rows[i].ItemArray[8].ToString();
                int      TrangThai    = Convert.ToInt32(datas.Rows[i].ItemArray[9].ToString());
                list.AddLast(new SanPham(MaSP, TenSP, SoLuong, NgayNhap, GiaNhap, GiaBan, GiamGia, SoLuongBanRa, LoaiSP, TrangThai));
            }
            return(list);
        }
 public static DataTable getAllDataTable()
 {
     return(SanPham_DB.getAllDataSanPham());
 }