The Second Com-based Cad Software Development Techniques

A great revolution on the global economy is going on with the development of information technology and computer internet technology. Meanwhile, opening international market entitles consumers more choices, the personality and diversity of consumer request adds the market's speed of change and hardness of detect. New technologies increase the changes of the market rabidly. The diversities and changes of the market offer more and more requests, to enterprises majored in design and manufacture, on the flexibility and adjustment to changing. Hence, the core technology of this professional CAD system is to accomplish the reassembling of a pertinent system, which is convenient to append and be modified, to meet the need of the market.The purpose of this paper is exploring the design software of 3D solid modeling-JhSolid with perfect function, high efficiency and reliable capability, as well as according with habits of project designers of our country. An application development toolkit for CAD software has been created, based on the knowledge of Microsoft COM (Component Object Model), the systematic frame of JhSolid and Windows platform. This paper briefly demonstrates the request offered by CAD developer to application development toolkit, on security, derivability, efficiency, system amalgamation, and relatively independency. It also demonstrates the application developer's requests on the openness, easiness to use, stability and self-determination.The specific works are mentioned like this:Deep research on the appearance, development, technological theory and characteristics of COM; The selection of COM as the key technology of Jhsolid software application development toolkit; Analysis on the connections and differences between dynamic link library (DLL) and COM; Development and accomplishment the application development toolkit basic on COM of JhSolid software system, including realization of COM interface, COM sever, and opened methods, which as well as development and realization of client programs basic on; Design, development and realization of the partial functions of application manager of Jhsolid software system.Worked out by the procedure, debugs and test repeatedly, it has verified that this procedure has succeeded in realizing above-mentioned functions, which prove the correctness and feasibility of this method.