1. 删除购物车中一个商品
1.1 产品原型
1.2 接口设计
1.3 数据模型
shopping_cart表：
-- auto-generated definition
create table shopping_cart
(id bigint auto_increment comment '主键'primary key,name varchar(32) null comment '商品名称',image varchar(255) null comment '图片',user_id bigint not null comment '主键',dish_id bigint null comment '菜品id',setmeal_id bigint null comment '套餐id',dish_flavor varchar(50) null comment '口味',number int default 1 not null comment '数量',amount decimal(10, 2) not null comment '金额',create_time datetime null comment '创建时间'
)
comment '购物车' collate = utf8_bin;
1.4 代码开发
1.4.1 ShoppingCartController
/*** 删除购物车中一个商品* @param shoppingCartDTO* @return
*/
@PostMapping("/sub")
@ApiOperation("删除购物车中一个商品")
public Result sub(@RequestBody ShoppingCartDTO shoppingCartDTO){log.info("删除购物车中一个商品，商品：{}", shoppingCartDTO);shoppingCartService.subShoppingCart(shoppingCartDTO);return Result.success();
}
1.4.2 ShoppingCartService
/*** 删除购物车中一个商品* @param shoppingCartDTO
*/
void subShoppingCart(ShoppingCartDTO shoppingCartDTO);
1.4.3 ShoppingCartServiceImpl
/*** 删除购物车中一个商品* @param shoppingCartDTO
*/
public void subShoppingCart(ShoppingCartDTO shoppingCartDTO) {ShoppingCart shoppingCart = new ShoppingCart();BeanUtils.copyProperties(shoppingCartDTO,shoppingCart);//设置查询条件，查询当前登录用户的购物车数据shoppingCart.setUserId(BaseContext.getCurrentId());List<ShoppingCart> list = shoppingCartMapper.list(shoppingCart);if(list != null && list.size() > 0){shoppingCart = list.get(0);Integer number = shoppingCart.getNumber();if(number == 1){//当前商品在购物车中的份数为1，直接删除当前记录shoppingCartMapper.deleteById(shoppingCart.getId());}else {//当前商品在购物车中的份数不为1，修改份数即可shoppingCart.setNumber(shoppingCart.getNumber() - 1);shoppingCartMapper.updateNumberById(shoppingCart);}}
}
1.4.4 ShoppingCartMapper
/*** 根据id删除购物车数据* @param id
*/
@Delete("delete from shopping_cart where id = #{id}")
void deleteById(Long id);
