如何将盘区从EPSG3857转换为EPSG 26331

Question

我正在尝试通过ol.proj.transformExtent(map.getView().calculateExtent(map.getSize())，'EPSG: 3857 '，‘EPSG: 26331’将3857投影中的范围转换为OpenLayers中的26331投影。)

Answer 1

您首先需要包含proj4js库

<script src="https://cdnjs.cloudflare.com/ajax/libs/proj4js/2.6.2/proj4.js"></script>

然后是来自https://epsg.io/26331的EPSG:26331 proj4js定义

proj4.defs("EPSG:26331","+proj=utm +zone=31 +ellps=clrk80 +towgs84=-92,-93,122,0,0,0,0 +units=m +no_defs");
ol.proj.proj4.register(proj4);  // if you are using OpenLayers 5 or 6

var transformedExtent = ol.proj.transformExtent(map.getView().calculateExtent(map.getSize()),'EPSG:3857','EPSG:26331');