The Application Of RIA Technology In Building WebGIS

After development of nearly 5 decades, GIS technology migrates from academic to mature application, and transferred from Client/Server architecture to Browser/Server architecture because of the widespread utilization of Internet. As the product of combination of GIS and Web, WebGIS has closely integrated into the mainstream of Web technology. The quantity of mature Rich Internet Application on the Web increased rapidly in recent years, and the numerous advantages of RIA make the integration of WebGIS and RIA as an inevitable fact.This paper outlined the trend of the combination of WebGIS and Web technology, including RIA, Mashup, and Cloud Computing, analyzed the advantages of Silverlight technology, and also discussed the necessity of the combination of the two. Then summarized the architecture and the advantage of ArcGIS Server software, and researched the base technology of RIA of WebGIS on that platform, including CallbackResult architecture of asynchronously communication, the technology of base map caching, and Representational State Transfer style web services. The paper also puts forward RIA solutions and implementations of traditional WebGIS functionalities, such as thematic mapping and charting, querying and analysis, map editing etc., based on ArcGIS API for Silverlight. In addition to these, paper brings forward the advantages and implementations of building RIA of WebGIS in Silverlight technology, including dynamic symbology and multiple datasource mashup, etc..Based on these, this paper elaborated Dynamic Segmentation Technology and the corresponding implementation of RIA of WebGIS, relyes on the work of building GIS sub-system of Decision Support System on Highway Maintenance in Shaanxi Province, finally completed the WebGIS sub-system by using Silverlight technology, with confirmation of feasibility of theories above.