protected void Page_Load(object sender, EventArgs e) { try { hienThanhPhamChon(); if (Session["dsThanhPhamChon"] == null) { lbDSChon.Visible = false; lbTextTongTien.Visible = false; lbTongTien.Visible = false; lbDSSanpham.Visible = false; grDSSanPham.Visible = false; gridDSChon.Visible = false; } else { lbDSChon.Visible = true; lbTextTongTien.Visible = true; lbTongTien.Visible = true; lbDSSanpham.Visible = true; grDSSanPham.Visible = true; gridDSChon.Visible = true; } } catch (Exception) { Response.Write("<script>alert('Loi tai du lieu!')</script>"); } if (IsPostBack == false)//postback=false: chưa có sự kiện click trên web { // request: yeu cau. QueryString: lay gia tri cua chuoi tren duong dan string makh = Request.QueryString["MaKH"].ToString(); DAO_Entity daoEntities = new DAO_Entity(); DTOKhachHang dtoKH = daoEntities.LayTTKHTheoMa(makh); XuLy_TiepNhanDonHang control = new XuLy_TiepNhanDonHang(); control.LayttKH(makh); lbMaKH.Text = dtoKH.MaKH.ToString(); txtTen.Text = dtoKH.TenKH; txtNgayTaoDH.Text = DateTime.Now.ToShortDateString(); List <DTODonDatHang> dsdh = daoEntities.LayDSDHTheoMa(makh); GridViewDH.DataSource = dsdh; GridViewDH.DataBind(); grDSSanPham.DataSource = daoEntities.TaoDSSP(); grDSSanPham.DataBind(); } }