OpenLayers 3 中来自 QGIS 服务器的 WFS

Posted 2023-03-25

【中文标题】OpenLayers 3 中来自 QGIS 服务器的 WFS

【英文标题】：WFS from QGIS Server in OpenLayers 3

【发布时间】：2016-08-15 13:36:41

【问题描述】：

我正在尝试使用 QGIS Server (2.14) 实现此示例 https://medium.com/@goldrydigital/wfs-t-with-openlayers-3-16-6fb6a820ac58 并适应不同的 SRS。不幸的是，函数 ol.format.WFS.readFeatures() 无法读取 QGIS 服务器发回的几何图形（参见 console.log(features[k].getGeometry()); // => NULL ))

非常感谢任何帮助，谢谢！

顺便说一句：使用 ArcGIS-Server-WFS 时，下面的代码可以正常工作...

代码：

var formatWFS = new ol.format.WFS();
var sourceWFS = new ol.source.Vector(
            loader: function (extent) 
                $.ajax('http://xxx/qgis/qgis_mapserv.fcgi.exe', 
                    type: 'GET',
                    data: 
                        service: 'WFS',
                        version: '1.0.0',
                        request: 'GetFeature',
                        typename: 'test2',
                        srsname: 'EPSG:2056',
                        bbox: extent.join(',') + ',EPSG:2056'
                    
                ).done(function (response) 
                        wfsresponsefeatures = formatWFS.readFeatures(response);
                                sourceWFS.addFeatures(wfsresponsefeatures);
                    features = sourceWFS.getFeatures();
                    for (var k in features) 
                        console.log(features[k].getGeometry()); // => NULL
                    

WFS 响应如下：

    <wfs:FeatureCollection xmlns:wfs="http://www.opengis.net/wfs" xmlns:ogc="http://www.opengis.net/ogc" xmlns:gml="http://www.opengis.net/gml" xmlns:ows="http://www.opengis.net/ows" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:qgs="http://www.qgis.org/gml" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.opengis.net/wfs http://schemas.opengis.net/wfs/1.0.0/wfs.xsd http://www.qgis.org/gml http://szhm4120/qgis/qgis_mapserv.fcgi.exe?srsname=EPSG%3A2056&amp;SERVICE=WFS&amp;VERSION=1.0.0&amp;REQUEST=DescribeFeatureType&amp;TYPENAME=test2&amp;OUTPUTFORMAT=XMLSCHEMA"><gml:boundedBy>
 <gml:Box srsName="EPSG:2056">
  <gml:coordinates cs="," ts=" ">2681188.02,1246449.97 2685167.35,1248977.27</gml:coordinates>
 </gml:Box>
</gml:boundedBy>
<gml:featureMember>
 <qgs:test2 fid="test2.2">
  <gml:boundedBy>
   <gml:Box srsName="EPSG:2056">
    <gml:coordinates cs="," ts=" ">2683250.99,1248618.11 2683250.99,1248618.11</gml:coordinates>
   </gml:Box>
  </gml:boundedBy>
  <qgs:geometry>
   <gml:Point srsName="EPSG:2056">
    <gml:coordinates cs="," ts=" ">2683250.99,1248618.11</gml:coordinates>
   </gml:Point>
  </qgs:geometry>
  <qgs:id>2</qgs:id>
 </qgs:test2>
</gml:featureMember>
<gml:featureMember>
 <qgs:test2 fid="test2.3">
  <gml:boundedBy>
   <gml:Box srsName="EPSG:2056">
    <gml:coordinates cs="," ts=" ">2681673.03,1247121.49 2681673.03,1247121.49</gml:coordinates>
   </gml:Box>
  </gml:boundedBy>
  <qgs:geometry>
   <gml:Point srsName="EPSG:2056">
    <gml:coordinates cs="," ts=" ">2681673.03,1247121.49</gml:coordinates>
   </gml:Point>
  </qgs:geometry>
  <qgs:id>3</qgs:id>
 </qgs:test2>
</gml:featureMember>
<gml:featureMember>
 <qgs:test2 fid="test2.6">
  <gml:boundedBy>
   <gml:Box srsName="EPSG:2056">
    <gml:coordinates cs="," ts=" ">2682779.23,1248227.69 2682779.23,1248227.69</gml:coordinates>
   </gml:Box>
  </gml:boundedBy>
  <qgs:geometry>
   <gml:Point srsName="EPSG:2056">
    <gml:coordinates cs="," ts=" ">2682779.23,1248227.69</gml:coordinates>
   </gml:Point>
  </qgs:geometry>
  <qgs:id>6</qgs:id>
 </qgs:test2>
</gml:featureMember>
</wfs:FeatureCollection>

【参考方案1】：

好的，所以 QGIS Server 只能为带有 GML2 几何图形的 WFS 1.0.0 提供服务...

以上示例通过将 WFS 设置为 GML2 来工作

var formatWFS = new ol.format.WFS(
    'gmlFormat': new ol.format.GML2
);