在Openlayers 3中选择要素(点、线、面)时自定义顶点样式？

// 创建一个样式函数来定义要素的样式
var styleFunction = function(feature) {
  var geometryType = feature.getGeometry().getType(); // 获取要素的几何类型

  // 根据几何类型自定义顶点样式
  if (geometryType === 'Point') {
    return new ol.style.Style({
      image: new ol.style.Circle({
        radius: 6,
        fill: new ol.style.Fill({color: 'red'}),
        stroke: new ol.style.Stroke({color: 'white', width: 2})
      })
    });
  } else if (geometryType === 'LineString') {
    return new ol.style.Style({
      stroke: new ol.style.Stroke({color: 'blue', width: 2}),
      image: new ol.style.RegularShape({
        fill: new ol.style.Fill({color: 'blue'}),
        stroke: new ol.style.Stroke({color: 'white', width: 2}),
        points: 4,
        radius: 6,
        angle: Math.PI / 4
      })
    });
  } else if (geometryType === 'Polygon') {
    return new ol.style.Style({
      fill: new ol.style.Fill({color: 'green'}),
      stroke: new ol.style.Stroke({color: 'white', width: 2}),
      image: new ol.style.RegularShape({
        fill: new ol.style.Fill({color: 'green'}),
        stroke: new ol.style.Stroke({color: 'white', width: 2}),
        points: 4,
        radius: 6,
        angle: Math.PI / 4
      })
    });
  }
};

// 创建一个矢量图层，并设置样式函数
var vectorLayer = new ol.layer.Vector({
  style: styleFunction
});

// 将矢量图层添加到地图中
map.addLayer(vectorLayer);