摘要： 在分析了原有结构CAD系统的基础上，进一步提出了基于两类层次的系统设计方案，在底层使用基于复合文件的工程数据库，在设计时根据模块自身不同的特点，加以区别对待。在模块内部使用面向对象的方法设计，在主要模块之间使用数据流的分析方法，对附属模块采用COM技术实现插件机制。

关键词: CAD, 组件, 工程数据库

Abstract: A system design scheme based on two kinds of level is presented on the analysis of former CAD system. On the background, the system uses engineering database which is constructed with compound document technology. This paper makes a difference between models for their different traits. Object-orient design method is approached inside the model while data stream analysis method is used between the main models. And a plug-in mechanism is applied for those minor models.

中图分类号: 

• TP391.72