关键词: 数据访问层, Entity Framework, 可扩展性, 接口, 高效, 延迟加载

Abstract: In the development process of large and medium-sized systems,in order to improve the scalability,reusability and maintainability of the system,multi-tier architecture is generally adopted.In the design of multi-tier architecture,the design of data access layer is particularly critical.Through the analysis and research of several open source frameworks,combined with theoretical thinking and practical development experience,the key technologies of optimizing data access layer step by step are analyzed and elaborated from making full use of code and interface reusability,reducing maintenance costs and improving software scalability.A set of universal data access layer technology is formed.At the same time,the code implemented by Entity Framework technology on.Net platform is given.Thus,it can deepen the understanding of common technical ideas of data access layer for software technology developers,and provide a technical reference for peers to implement data access layer.Practice shows that the system using this data access layer technology in multi-tier architecture system has the characteristics of high decoupling,high expansion,high availability and high development efficiency,and has a wide application prospect.

Key words: data access layer, Entity Framework, extensibility, interface, high efficiency, delayed loading