Overview of. NET Open Source GIS Solutions

Write in front

Recently began to study open source GIS, the domestic open source GIS data is very few, but is based on. NET is few. So decided to summarize their research data, technology is to share, this series (the plan is to write a series, if I can stick to the words) part of their own summary, partly from the network excerpt.

Technical Solutions

The main demand is to use B/s architecture, the front-end display map, and to achieve the figure (Point line surface) of the deletion and modification, as well as property pickup and editing. The whole solution is probably made up of these parts (personally): map data, GIS servers, GIS middleware (GIS class libraries), Web servers and clients.

Web server

Because of the. NET environment, the Web server must be IIS.

GIS Middleware

Although the GIS server can also implement some basic functions, but the use of open-source GIS library, more scalable, operational data, data analysis is more convenient, and can be ported to C/s program. For Java, the mainstream is geotools, and. NET is the best choice is dotspatial, the source code is written in C #. Dotspatial is an open source GIS library based on. NET 4, which provides a visual map control that can be displayed on a Windows Form or Web application. It can easily support the reading and writing of shapefiles, grids and other raster/image data, and in the aspect of graphics rendering, it provides a lot of practical interfaces, and developers can fully customize the rendering effect of the map. Support the projection processing of data and some common analysis functions.

Map data

There are two kinds, one is the file storage, directly in the form of shapefiles files, and the other is the use of spatial database. In the open source spatial database, the Postgis,mysql spatial and spatialite are compared. PostGIS is an extension module for open source database PostgreSQL, Spatialite is an extension module for SQLite, and MySQL spatial is an extension module for open source database MySQL. In comparison, in the field of open source GIS, PostGIS can get more extensive support, but because dotspatial seemingly only support spatiite, so can only choose Spatiite. For data editing, you can use Qgis (written in C + +) or Mapwindow 6 (based on dotspatial development)

GIS Server

GeoServer or MapServer. GeoServer is a community open source project implemented by the Java OpenGIS WEB Server specification, MapServer is based on C. Personal feeling GeoServer is more powerful in function, while MapServer seems to be more efficient in processing large amounts of data. About the comparison between the two. So personal choice Geoserver,geoserver native is not supported spatialite, need to install the extension, here is the tutorial.

Client

The mainstream is openlayers. Openlayers is a JavaScript package for developing WEBGIS clients. Openlayers supported map sources including Google Maps, Yahoo, map, Microsoft virtual Earth, etc., users can also use a simple image map as a background map, and other layers in the openlayers overlay, Openlayers offers a great many options in this regard. In terms of operations, openlayers can help developers in the browser to achieve the basic effect of map browsing, such as zooming in, zoom out, panning (pan) and other common operations, but also the selection of polygons, selection lines, feature selection, layer overlays and other different operations , you can even extend the existing openlayers operations and data support types to give them more functionality.

Overview of. NET Open Source GIS Solutions