销售管理系统是基于B/S三层架构，用C#语言实现实现的主要功能是查询进货，销售情况，添加和查询公司物品和进货情况，增添用户信息-Sales management system is based on B/S three-tier structure, with the C# language to achieve the main function is to check the purchase, sale, and query the company to add items and pur