本文以广东省行政区划为例介绍如何使用矢量图形数据导出可以在高德百度等互联网地图上加载的省级行政区划边界JSON数据。
第一步用GIS相关工具,如ArcGIS、MapGIS、QGIS等工具加载广东省域的矢量边界,然后导出广东省的矢量边界为GeoJson格式,下面以ArcGIS为例。
(1)在ArcGIS中加载广东省行政区划边界,加载后显示如下图。
(2)依次进入ArcGIS工具箱、转换工具、JSON、要素转JSON。
(3)打开要素转JSON的工具对话框,选择需导出为JSON数据的矢量图层,再选择导出数据的存放地址,如果是要加载到如百度、高德等的互联网地图上,则选择导出为“输出至GeoJSON”,根据需要选择“投影到WGS84”即可。
(4)导出的GeoJSON数据结构如下图所示,分别包括图形的坐标串、矢量图形的各项属性字段等内容,本数据即可通过代码开发方式引用到地图上加载。
{"type": "FeatureCollection","features": [{"type": "Feature","id": 0,"geometry": {"type": "MultiPolygon","coordinates": [[[[117.13124847400002,23.39889000088],[117.12985992400002,23.397079468000072],[117.13180542000009,23.395971298000063]]]]},"properties": {"FID": 0,"ID_2": 43,"CP": [116.7812478,23.7828454],"NAME_2": "Chaozhou","NL_NAME_2": "潮州市","VARNAME_2": "Cháozhōu"}},{"type": "Feature","id": 1,"geometry": {"type": "Polygon","coordinates": [[[113.59436035200008,23.111679077000076],[113.58190155,23.101413727000079],[113.57511138900009,23.098817825000083]]]},"properties": {"FID": 1,"ID_2": 44,"CP": [113.8765055, 22.9361511],"NAME_2": "Dongguan","NL_NAME_2": "东莞市","VARNAME_2": "Dōngguǎn"}}}