public ActionResult EditingCustomValidation_Update([DataSourceRequest] DataSourceRequest request, CustomValidationProductViewModel product)
        {
            if (product != null && ModelState.IsValid)
            {
                productService.Update(new ProductViewModel
                {
                    ProductID = product.ProductID,
                    ProductName = product.ProductName,
                    UnitPrice = product.UnitPrice
                });
            }            

            return Json(new[]{product}.ToDataSourceResult(request,ModelState));
        }        
        public ActionResult EditingCustomValidation_Update([DataSourceRequest] DataSourceRequest request, CustomValidationProductViewModel product)
        {
            if (product != null && ModelState.IsValid)
            {
                var target = SessionProductRepository.One(p => p.ProductID == product.ProductID);
                if (target != null)
                {
                    target.ProductName = product.ProductName;
                    target.UnitPrice = product.UnitPrice;
                    SessionProductRepository.Update(target);
                }
            }

            return Json(ModelState.ToDataSourceResult());
        }