public async Task <IActionResult> Put(int id, [FromBody] ProductModificationViewModel productVm)
        {
            if (productVm == null)
            {
                return(BadRequest());
            }

            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }
            var dbItem = await _productRepository.GetSingleAsync(id);

            if (dbItem == null)
            {
                return(NotFound());
            }
            Mapper.Map(productVm, dbItem);
            _productRepository.Update(dbItem);
            if (!await UnitOfWork.SaveAsync())
            {
                return(StatusCode(500, "保存时出错"));
            }

            return(NoContent());
        }
        public IActionResult Put([FromBody] ProductModificationViewModel productModificationViewModel, int id)
        {
            if (productModificationViewModel == null)
            {
                return(BadRequest());
            }
            if (productModificationViewModel.Name == "产品")
            {
                ModelState.AddModelError("Name", "名称不可以是产品");
            }
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }
            var model = _productRepository.GetProduct(id, false);

            if (model == null)
            {
                return(NotFound());
            }
            //Mapper.Map<Product>(productModificationViewModel);//只是映射值,但并没有改变model的状态,所以持久化到数据库仍然没有变化
            Mapper.Map(productModificationViewModel, model);//把第一个参数的值赋值到第二个参数上,并修改第二个参数的状态为modified,使之可以随DbContext持久化到DB
            if (!_productRepository.Save())
            {
                return(StatusCode(500, "更新出错"));
            }
            //var model = ProductServicesMemory.productServices.products.Find(x => x.Id == id);
            //if (model == null)
            //    return NotFound();
            //model.Name = productModificationViewModel.Name;
            //model.Price = productModificationViewModel.Price;
            return(NoContent());
        }