Silverlight-based Webgis Development Research

WebGIS is a combination of GIS and Web technology whose emergence greatly make GIS popular in more fields and applications. Recently, traditional WebGIS make a huge progress both in theory and practice. However, due to the use of HTML page, traditonal WebGIS meets problems as follows: poor user interface, slow response time, poor interactive capability. What'more, problems accelerates in the development of traditionan WebGIS owing to the use of SOAP style Web Service, such as complicated development and difficult system maintenace.Fortunately, most of difficulties in tradionnal Web GIS are overcamed thanks to the coming of RIA and REST technology which brings new chances and energy to the the development of WebGIS. Now, WebGIS based on RIA becomes a popular trend and research hot-field in the development of GIS. Silverlight is a cross-brower and cross-platform RIA plug-in invented by Microsoft which has a richful user expierence and powerful functions. ArcGIS Server is a excellent WebGIS software. ArcGIS Server based on Silverlight not only has the advantage of powerful Silverlight platform and powerful ArcGIS platform but also has the advantage of light REST style Web Service. System developed by this style has a beautiful user interface, rapid response time, easy deployment and high developing efficiency, so this developing style has great potential and a good future.The merits and technology attributes of ArcGIS Server, REST style Web service and Siverlight is analysised in this dissertation. The merit and usage of ArcGIS Server REST API and ArcGIS API for Silverlight are studied and illustrated in great details. After these, the road-map of ArcGIS Server development with Silverlight is studed. The project named Kunming Traffic Control System have been comepleted based on Silverlight and ArcGIS Server as a demo to show how this method works. Geodatabase of the practice system is designed in the project, either. In the project, GIS web services are published by ArcGIS Server 9.3 in the sever side and the Silverlight client side consumes these services with REST API. Some functions are accomplished in the project, such as map exploring and zooming, map measuring, traffic feature finding and buffering analysis etc.According the developing practice, WebGIS based on Silverlight runs smoothly and has a very beautiful user interfaces. The Silverlight-based WebGIS system has greater advantage than traditional HTML-page-based WebGIS system in the ways like response time, graphic display, animation effects, multimedia intergration, etc. In addtion, this developing style uses lightly REST style Web Service. Thus, this developing stytle has very good prospects.