11.更新和删除购物车

表现层

    
    /**
     * 更新购物车
     */
    public E3Result updateCartNum(long userId, long itemId, int num) {
        //根据用户id查询用户列表
        String json = jedisClient.hget(REDIS_CART_PRE+":"+userId, itemId+"");
        //更新商品数量
        TbItem item = JsonUtils.jsonToPojo(json, TbItem.class);
        item.setNum(num);
        //写入Redis 
        jedisClient.hset(REDIS_CART_PRE+":"+userId, itemId+"",JsonUtils.objectToJson(item));
        return E3Result.ok();
    }

    /**
     * 删除购物车
     */
    public E3Result deleteCartItem(long userId, long itemId) {
        //根据用户id查询用户列表
        jedisClient.hdel(REDIS_CART_PRE+":"+userId, itemId+"");
        return E3Result.ok();
    }

表现层的实现

/**
     * 更新购物车商品的数量
     */
    @RequestMapping("/cart/update/num/{itemId}/{num}")
    @ResponseBody
    public E3Result updateCatNum(@PathVariable Long itemId,@PathVariable Integer num,
            HttpServletRequest request,HttpServletResponse response){
        //判断用户是否登录
        TbUser user = (TbUser) request.getAttribute("user");
            if(user !=null){
                cartService.updateCartNum(user.getId(), itemId, num);
                return E3Result.ok();
            }
        //1.取出购物车的列表
        List<TbItem> itemList = getCartListFromCookie(request);
        //2.遍历列表,找到对应的商品
        for(TbItem item :itemList){
            if(item.getId().longValue() == itemId){
                //3.更新数量
                item.setNum(num);
                break;
            }
        }
        //4.把购物车列表写回Cookie
        CookieUtils.setCookie(request, response,"cart",JsonUtils.objectToJson(itemList),COOKIE_CART_EXPIRE,true);
        //5.返回成功
        return E3Result.ok();
        
    }
    
    /**
     * 删除购物车商品
     */
    @RequestMapping("/cart/delete/{itemId}")
    public String deleteCartItem(@PathVariable Long itemId, HttpServletRequest request,
            HttpServletResponse response) {
        //判断用户是否为登录状态
        TbUser user = (TbUser) request.getAttribute("user");
        //如果是登录状态,把购物车写入Redis
        if (user != null) {
            //保存到服务器
            cartService.deleteCartItem(user.getId(), itemId);
            //返回逻辑视图
            return "redirect:/cart/cart.html";
        }
        //从cookie中取购物车列表
        List<TbItem> cartList = getCartListFromCookie(request);
        //遍历列表，找到要删除的商品
        for (TbItem tbItem : cartList) {
            if (tbItem.getId().longValue() == itemId) {
                //删除商品
                cartList.remove(tbItem);
                //跳出循环
                break;
            }
        }
        //把购物车列表写入cookie
        CookieUtils.setCookie(request, response, "cart", JsonUtils.objectToJson(cartList), COOKIE_CART_EXPIRE, true);
        //返回逻辑视图,跳转到下面的页面
        return "redirect:/cart/cart.html";
    }

观察结果

图片.png
图片.png