原文链接及内容

原文链接：https://openlayers.org/en/latest/examples/icon.html

运行界面

使用一个图标来符号化一个点要素的示例。

main.js代码如下：

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import Feature from 'ol/Feature.js';
import Map from 'ol/Map.js';
import Overlay from 'ol/Overlay.js';
import Point from 'ol/geom/Point.js';
import TileJSON from 'ol/source/TileJSON.js';
import VectorSource from 'ol/source/Vector.js';
import View from 'ol/View.js';
import {Icon, Style} from 'ol/style.js';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer.js';

const iconFeature = new Feature({
  geometry: new Point([0, 0]),
  name: 'Null Island',
  population: 4000,
  rainfall: 500,
});

const iconStyle = new Style({
  image: new Icon({
    anchor: [0.5, 46],
    anchorXUnits: 'fraction',
    anchorYUnits: 'pixels',
    src: 'data/icon.png',
  }),
});

iconFeature.setStyle(iconStyle);

const vectorSource = new VectorSource({
  features: [iconFeature],
});

const vectorLayer = new VectorLayer({
  source: vectorSource,
});

const rasterLayer = new TileLayer({
  source: new TileJSON({
    url: 'https://a.tiles.mapbox.com/v3/aj.1x1-degrees.json?secure=1',
    crossOrigin: '',
  }),
});

const map = new Map({
  layers: [rasterLayer, vectorLayer],
  target: document.getElementById('map'),
  view: new View({
    center: [0, 0],
    zoom: 3,
  }),
});

const element = document.getElementById('popup');

const popup = new Overlay({
  element: element,
  positioning: 'bottom-center',
  stopEvent: false,
});
map.addOverlay(popup);

let popover;
function disposePopover() {
  if (popover) {
    popover.dispose();
    popover = undefined;
  }
}
// display popup on click
map.on('click', function (evt) {
  const feature = map.forEachFeatureAtPixel(evt.pixel, function (feature) {
    return feature;
  });
  disposePopover();
  if (!feature) {
    return;
  }
  popup.setPosition(evt.coordinate);
  popover = new bootstrap.Popover(element, {
    placement: 'top',
    html: true,
    content: feature.get('name'),
  });
  popover.show();
});

// change mouse cursor when over marker
map.on('pointermove', function (e) {
  const pixel = map.getEventPixel(e.originalEvent);
  const hit = map.hasFeatureAtPixel(pixel);
  map.getTarget().style.cursor = hit ? 'pointer' : '';
});
// Close the popup when the map is moved
map.on('movestart', disposePopover);

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>Icon Symbolizer</title>
    <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@5.2.0/dist/css/bootstrap.min.css">
    <link rel="stylesheet" href="node_modules/ol/ol.css">
    <style>
      .map {
        width: 100%;
        height: 400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"><div id="popup"></div></div>
    <!-- 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 src="https://cdn.jsdelivr.net/npm/bootstrap@5.2.0/dist/js/bootstrap.bundle.min.js"></script>
    <script type="module" src="main.js"></script>
  </body>
</html>