“面向区域”的GIS控件的设计与使用

The design and usage of regionally-oriented GIS controller

本文提出了一个“面向区域”GIS控件的概念———即以特定的地理区域为对象 ,将基础地理信息连同有关的GIS功能操作融合为一个可重用的程序模块 ,以Microsoft的COM (即“组件对象模型”)技术为基础 ,组织为“GIS化”的ActiveX控件。这种GIS控件 ,将面向对象技术中的“对象”扩展到了整个特定的地理区域空间 ,其核心思想是不仅封装了GIS的数据模型 ,必要的功能操作 ,而且封装了所有的基础地理信息。由于省去了对空间数据的处理 ,因而这种GIS控件可被广大非GIS专业的信息系统开发者灵活、简便地用于各种管理信息系统、办公自动化系统和决策支持系统的GIS功能扩充 ,也可用于构建一般的地理信息系统 ,因而有利于GIS技术应用的普及。

The present paper introduces the concept of “regionally based” GIS controller which applies general GIS operational functions to specific geographical regions and creates a new program module Using the techniques of Microsoft's COM(component object model), this module is ActiveX controller based on GIS The controller is a macro level extension of object technology in GIS Its essence is that it not only packaged the data module of GIS as well as the necessary functional operations, but also packaged all of the basic geographical information With this GIS controller, the user does not have to create his own geographical data base and process spatial data He can easily look up and display geographical data for his own purposes, spatially calculate such data, process them, categorize and turn them into graphic form, to name just a few of the functions By combining the geographic object of controller with his own data, the user can conveniently use the various GIS functions for systematic development of specific geographic regions Since there is no need to put in and process spatial data, this GIS controller is especially suitable for non GIS specialists in the management of various information systems, in automatic office management and in the functional GIS extension of support systems for decision making This is a new direction of development in the application of GIS This paper explores the organizational techniques and development methods in this “regionally based” GIS controller It examines the key points in the spatial data module and the data base and the main features and techniques of the controller Finally, this paper provides two cases of application, “the Shaanxi Environmental Database System”and “Shaanxi Population GIS System”