py mysql结合面向对象，实现类似超市导购机器的功能【5.商品种类】

    def run(self):
        while True:
            print(‘-----商品种类-----‘)
            print(‘1.查看所有商品种类‘)
            print(‘2.查看每种商品种类下的所有商品信息‘)
            print(‘3.根据商品种类查询商品信息‘)
            print(‘4.返回上一级‘)
            num = input(‘请输入操作类型：‘)
            if num == ‘1‘:
                # 查看所有商品种类
                sql = """select * from goods_cates"""
                count = self.cs1.execute(sql)
                print(‘共计搜索到%s条商品种类信息‘ % count)
                goods_cates_info = self.cs1.fetchall()
                for temp in goods_cates_info:
                    t_len = len(temp)
                    for i in range(t_len):
                        if i == t_len - 1:
                            print(‘分类:%s‘ % temp[i])
                        else:
                            print(‘CateID:%d‘ % temp[i], end=‘,‘)

            elif num == ‘2‘:
                # 查看每种商品种类下的所有商品信息
                sql = """select c.name,group_concat(g.name,‘ ‘,b.name,‘ ‘,price) 
                            from goods as g ,goods_cates as c,goods_brands as b 
                            where g.cate_id=c.id and g.brand_id=b.id group by c.id;"""
                count = self.cs1.execute(sql)
                print(‘共计搜索到%s个商品种类‘ % count)
                cates_goods = self.cs1.fetchall()
                for temp in cates_goods:
                    t_len = len(temp)
                    for i in range(t_len):
                        if i == t_len - 1:
                            print(temp[i])
                        else:
                            print(temp[i], end=‘:‘)

            elif num == ‘3‘:
                # 根据商品种类查询商品信息
                find_cate = input(‘请输入要查询的商品类别名称:‘)
                args = ‘%‘ + find_cate + ‘%‘
                sql = """select g.name,c.name,b.name,g.price from goods as g
                                    inner join goods_cates as c on g.cate_id=c.id 
                                    inner join goods_brands as b on g.brand_id=b.id 
                                    having c.name like %s;"""
                count = self.cs1.execute(sql, args)
                print(‘共计搜索到%s类别下%s个商品信息‘ % (find_cate, count))
                find_goods_info = self.cs1.fetchall()
                for temp in find_goods_info:
                    t_len = len(temp)
                    for i in range(t_len):
                        if i == t_len - 1:
                            print(temp[i], ‘元‘)
                        else:
                            print(temp[i], end=‘，‘)

            elif num == ‘4‘:
                # 返回上一级
                break
            else:
                print(‘操作模块选择错误，请重新输入‘)