基于HTML5的WebGIS研究

发布时间：2019-03-02 20:56

【摘要】：WebGIS是网络技术和GIS技术相结合的产物，它推动了GIS在更大范围内的应用和普及。同时网络技术的发展也促进了WebGIS的发展。通常为了实现一个交互能力强、用户体验好的WebGIS会运用到的Flex、Silverlight等技术，而更多的摒弃HTML技术。但是随着HTML5标准的发布，WebGIS的发展又出现了一个新的契机。因为HTML5以无插件的方式提供很多的API提高了网页的交互能力和用户体验能力以达到甚至更优于Flex等技术。本文结合HTML5的良好的特性做了如下工作：首先，论文详述了HTML5的特性。根据这些特征选用了服务器端与客户端相结合的混合构造模式，作为实现基于HTML5的WebGIS的构造模式。深入分析了OGC的Web地理信息服务，，尤其是讨论了如何使用Filter Encoding进行空间数据的过滤输出。其次，本文对比并分析了WebSocket技术和Ajax技术，并总结出了它们各自在WebGIS的使用范围。另外，结合HTML5支持本地存储功能本文初步的实现了一个支持空间矢量数据的缓存，加速矢量数据的获取和显示。第三，使用JavaScript语言对CanvasAPI进行面向对象封装，封装成不同的要素类，这样便于地图的绘制和管理，也降低CanvasAPI使用的难度。由于Canvas中绘制的图形不存在于网页的DOM中，于是模拟2级DOM事件实现Canvas中图形要素对事件的响应。另外分别使用服务器端方法和客户端方法实现了缓冲区分析并进行了简单的比较。最后，结合上述研究开发一个基于HTML5的Web地理信息原型系统。系统采用PHP和JavaScript作为开发语言，使用Apache作为Web服务器，并采用了以PostGIS作为数据源GeoServer作为空间服务器。论文通过基于HTML5的WebGIS的实现，验证了HTML5技术的在地理信息中的应用，通过系统的运行发现了系统存在的不足，提出了对今后研究工作的展望。
[Abstract]:WebGIS is a combination of network technology and GIS technology. It promotes the application and popularization of GIS in a wider range. At the same time, the development of network technology also promotes the development of WebGIS. Generally, in order to achieve a strong interactive ability, good user experience of WebGIS will be used in the Flex,Silverlight and other technologies, and more abandoned HTML technology. However, with the release of HTML5 standard, there is a new opportunity for the development of WebGIS. Because HTML5 provides a lot of API in a non-plug-in way, it improves the interactive ability and user experience ability of web pages to achieve or even better than Flex and other technologies. In this paper, the good characteristics of HTML5 are described as follows: firstly, the characteristics of HTML5 are described in detail. According to these characteristics, the hybrid construction pattern of server-side and client-side is selected as the construction pattern of implementing WebGIS based on HTML5. This paper deeply analyzes the Web geographic information service of OGC, especially discusses how to use Filter Encoding to filter spatial data. Secondly, this paper compares and analyzes the WebSocket technology and the Ajax technology, and summarizes the scope of their use in WebGIS. In addition, combined with the local storage function of HTML5, a cache of spatial vector data is preliminarily implemented to accelerate the acquisition and display of vector data. Thirdly, we use JavaScript language to encapsulate CanvasAPI object-oriented and encapsulate it into different feature classes, which is convenient for map drawing and management, and also reduces the difficulty of using CanvasAPI. Since the graphics drawn in Canvas do not exist in the DOM of web pages, the response of graphic elements to events in Canvas is realized by simulating the level 2 DOM events. In addition, the buffer analysis is implemented using server-side method and client-side method, and a simple comparison is made. Finally, a Web geographic information prototype system based on HTML5 is developed based on the above research. The system uses PHP and JavaScript as the development language, Apache as the Web server, and PostGIS as the data source, GeoServer as the spatial server. Through the implementation of WebGIS based on HTML5, this paper verifies the application of HTML5 technology in geographic information, finds out the shortcomings of the system through the operation of the system, and puts forward the prospect of future research work.
【学位授予单位】：江西理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P208;TP311.52

【参考文献】