Design And Implementation Of WebGIS Framework Based On .NET Platform

WebGIS is a computer geographic information system which is used to store, analyze, process, render and make better use of geographic data information in the internet/intranet network environment, and the basic idea of it is to provide the functionality of publishing and sharing the geographic information in the internet, so the clients could get geographic data and kinds of GIS services with ease, and then implement the requirements of GIS information inquiring and business processing based on Web.The aim of this thesis is to enhance the user experience of terminal users, and make it more simple and effective for publishing of geographic information, data sharing and interoperability, and meanwhile it could provide better interactivity for the communication between the client-side and server-side. Based on these goals, it apply GIS and computer technology, combining with server-side component and Ajax technologies of client-side, designing and developing a set of WebGIS framework based on.NET platform and it's reusable and based on component model. The goal of this framework is to render and analyse geospatial data in the form of high-definition and visual effect, making the development of GIS application based on Web more simple and rapidly, and providing better development pattern for developers, and so supplying more friendly and smooth user experience for end users.WebGIS framework is comprised of three parts:componentization client-side WebGIS framework, map rendering engine based on.NET platform, server-side WebGIS framework. This thesis introduces all things related with the WebGIS framework from the elementary to profound. First off, it tells us the basic concept, features and basic principle of WebGIS, and also sum up the requirements of functionality and data source for this framework, and then give us a detailed description about the infrastructure of this framework, communication model between client and server side; it also elaborate the theory, detailed implementation and its application for the Tiling technology, Web Map Service and map rendering engine. In addition, in orde to speed up the reponse time of map rendering, it puts forward the idea of pre-generating tile map, and the tile-pyramid model, directory hierarchy structure and its implemention or practical application related with it are also presented.Finally, this thesis introduces the ligh-weight Fleet Tracker system which is implemented by this WebGIS framework based on.NET platform, including its project background information, structure design of functionality and the application of the client and server side WebGIS framework.