Design And Research Of A WebGIS System Which Based On Flex And ArcGISServer

WebGIS is a computer system in Internet or Intranet environment to realize acquisition,storage,query,analysis,display and output of geographical information. It is an important direction of GIS development,and its prominent feature is to achieve dynamic links between graphic,image data and attribute data in spatial framework, to provide visual query and spatial analysis functionalities. However, with the development of network technology and increasingly use of GIS in all sectors, the traditional WebGIS has exposed a series of shortcomings such as poor user experience and interactivity,simple GUI,insufficient utilization of client computing resource, slow response and so on. It can't satisfy users'demand for new generation of WebGIS. But the emergence of RIA (Rich Internet Application) technology based on Flex has brought new opportunities to development of WebGIS. It can create a smart client which owns richer GUI, is more interactive and responsive, and is able to take full advantage of client computing resources. Meanwhile, ArcGIS Server, as an enterprise GIS server platform, has advanced GIS functionalities, which can publish a wide range of Web based GIS services to support geographical data management, geoprocessing, spatial analysis and other functionalities in distributed environment in order for local or Internet users to use. It provides a powerful solution for the server-side technology of WebGIS application. Thus, combination of Flex technology and ArcGIS Server make it possible to build the new generation of WebGIS.This article has fully studied the Flex technology, and designed a general framework for WebGIS based on advantages of Flex building web application and enterprise GIS server platform-ArcGIS Server. It also elaborates on the hierarchical structure, the composition and the reciprocity of this framework and gives implementation. On this basis, we have completed a WebGIS system, the Control point query system of Jiangsu Province. This system uses Adobe Flex Builder to construct smart client, ArcGIS Server 9.3.1 platform as GIS server to publish GIS resources providing advanced GIS functionalities and client interact with server through ArcGIS REST API. Compared with the traditional WebGIS, the system has a rich GUI similar to desktop operating environment, real time to reflect and interact component-based client which has strong scalability and reusability; ArcGIS Server-based multiple map services and Flash Remoting communication technology have greatly increased the speed of spatial data publishing and browsing. It provides a new way to construct WebGIS application. The results show that, the combination of Flex and ArcGIS Server has a broad prospect in WebGIS application.