原文链接及内容

原文链接：https://openlayers.org/en/latest/examples/select-features.html

运行界面

在Single-click、Click、Hover和Alt + Click之间进行选择，作为在下拉框中进行选择的事件类型。当使用Single-click或Click时，您可以按住Shift键来切换所选内容中的功能。

注意: Single-click时使用双击不会选择要素，这与Click相反，在Click中，双击既可以选择要素，又可以缩放地图(因为存在DoubleClickZoom交互)。注意，Single-click比Click响应慢，因为它用来检测双击的延迟。

在此示例中，为Select交互的select事件注册了一个侦听器，以更新上面的选择状态。

main.js代码如下：

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import GeoJSON from 'ol/format/GeoJSON.js';
import Map from 'ol/Map.js';
import Select from 'ol/interaction/Select.js';
import VectorLayer from 'ol/layer/Vector.js';
import VectorSource from 'ol/source/Vector.js';
import View from 'ol/View.js';
import {Fill, Stroke, Style} from 'ol/style.js';
import {altKeyOnly, click, pointerMove} from 'ol/events/condition.js';

const style = new Style({
  fill: new Fill({
    color: '#eeeeee',
  }),
});

const vector = new VectorLayer({
  source: new VectorSource({
    url: 'https://openlayers.org/data/vector/ecoregions.json',
    format: new GeoJSON(),
  }),
  background: 'white',
  style: function (feature) {
    const color = feature.get('COLOR') || '#eeeeee';
    style.getFill().setColor(color);
    return style;
  },
});

const map = new Map({
  layers: [vector],
  target: 'map',
  view: new View({
    center: [0, 0],
    zoom: 2,
  }),
});

let select = null; // ref to currently selected interaction

const selected = new Style({
  fill: new Fill({
    color: '#eeeeee',
  }),
  stroke: new Stroke({
    color: 'rgba(255, 255, 255, 0.7)',
    width: 2,
  }),
});

function selectStyle(feature) {
  const color = feature.get('COLOR') || '#eeeeee';
  selected.getFill().setColor(color);
  return selected;
}

// select interaction working on "singleclick"
const selectSingleClick = new Select({style: selectStyle});

// select interaction working on "click"
const selectClick = new Select({
  condition: click,
  style: selectStyle,
});

// select interaction working on "pointermove"
const selectPointerMove = new Select({
  condition: pointerMove,
  style: selectStyle,
});

const selectAltClick = new Select({
  style: selectStyle,
  condition: function (mapBrowserEvent) {
    return click(mapBrowserEvent) && altKeyOnly(mapBrowserEvent);
  },
});

const selectElement = document.getElementById('type');

const changeInteraction = function () {
  if (select !== null) {
    map.removeInteraction(select);
  }
  const value = selectElement.value;
  if (value == 'singleclick') {
    select = selectSingleClick;
  } else if (value == 'click') {
    select = selectClick;
  } else if (value == 'pointermove') {
    select = selectPointerMove;
  } else if (value == 'altclick') {
    select = selectAltClick;
  } else {
    select = null;
  }
  if (select !== null) {
    map.addInteraction(select);
    select.on('select', function (e) {
      document.getElementById('status').innerHTML =
        ' ' +
        e.target.getFeatures().getLength() +
        ' selected features (last operation selected ' +
        e.selected.length +
        ' and deselected ' +
        e.deselected.length +
        ' features)';
    });
  }
};

/**
 * onchange callback on the select element.
 */
selectElement.onchange = changeInteraction;
changeInteraction();

界面布局文件index.html代码如下：

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<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Select Features</title>
    <link rel="stylesheet" href="node_modules/ol/ol.css">
    <style>
      .map {
        width: 100%;
        height: 400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <form>
      <label for="type">Action type &nbsp;</label>
      <select id="type">
        <option value="click" selected>Click</option>
        <option value="singleclick">Single-click</option>
        <option value="pointermove">Hover</option>
        <option value="altclick">Alt+Click</option>
        <option value="none">None</option>
      </select>
      <span id="status">&nbsp;0 selected features</span>
    </form>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://cdn.jsdelivr.net/npm/elm-pep@1.0.6/dist/elm-pep.js"></script>
    <script type="module" src="main.js"></script>
  </body>
</html>