private void Bind()
 {
     if (!string.IsNullOrWhiteSpace(Request.QueryString["productItemId"]))
     {
         Guid productItemId = Guid.Empty;
         Guid.TryParse(Request.QueryString["productItemId"], out productItemId);
         if (!productItemId.Equals(Guid.Empty))
         {
             ProductDetail bll   = new ProductDetail();
             var           model = bll.GetModel(productId, productItemId);
             if (model != null)
             {
                 hAction_ProductDetail.Value = Request.QueryString["action"];
                 var li = ddlProductItem.Items.FindByValue(model.ProductItemId.ToString());
                 if (li != null)
                 {
                     li.Selected = true;
                 }
                 txtOriginalPrice.Value  = model.OriginalPrice.ToString();
                 txtProductPrice.Value   = model.ProductPrice.ToString();
                 txtDiscount.Value       = model.Discount.ToString();
                 txtDiscountDescri.Value = model.DiscountDescr;
                 txtaContent.Value       = model.ContentText;
             }
         }
     }
 }