var styles = {      'Polygon': [new ol.style.Style({        stroke: new ol.style.Stroke({          color: '#ff3100',          lineDash: [0],          width: 1        }),        fill: new ol.style.Fill({          color: 'rgba(0, 0, 255, 0.1)'        })      })],    };    var styleFunction = function(feature) {      console.log(feature)      return styles[feature.getGeometry().getType()];    };    var geojsonObject = {      'type': 'FeatureCollection',      'crs': {        'type': 'name',        'properties': {          'name': 'EPSG:3857'        }      },      'features': [        {        //区域          'type': 'Feature',          'geometry': {            'type': 'Polygon',            'coordinates': [              [                .........              ]            ]          }        },      ]    };    var vectorSource = new ol.source.Vector({      features: (new ol.format.GeoJSON()).readFeatures(geojsonObject)    });    var vectorLayer = new ol.layer.Vector({      source: vectorSource,      style: styleFunction,    });

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