The design and usage of regionally-oriented GIS controller

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”