原文链接及内容

原文链接：https://openlayers.org/en/latest/examples/draw-and-modify-features.html

运行界面

这是一个将ol/interaction/Draw绘制交互组件与ol/interaction/Modify修改交互组件一起使用的示例。

main.js代码如下：

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import Map from 'ol/Map.js';
import View from 'ol/View.js';
import {Draw, Modify, Snap} from 'ol/interaction.js';
import {OSM, Vector as VectorSource} from 'ol/source.js';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer.js';
import {get} from 'ol/proj.js';

const raster = new TileLayer({
  source: new OSM(),
});

const source = new VectorSource();
const vector = new VectorLayer({
  source: source,
  style: {
    'fill-color': 'rgba(255, 255, 255, 0.2)',
    'stroke-color': '#ffcc33',
    'stroke-width': 2,
    'circle-radius': 7,
    'circle-fill-color': '#ffcc33',
  },
});

// Limit multi-world panning to one world east and west of the real world.
// Geometry coordinates have to be within that range.
const extent = get('EPSG:3857').getExtent().slice();
extent[0] += extent[0];
extent[2] += extent[2];
const map = new Map({
  layers: [raster, vector],
  target: 'map',
  view: new View({
    center: [-11000000, 4600000],
    zoom: 4,
    extent,
  }),
});

const modify = new Modify({source: source});
map.addInteraction(modify);

let draw, snap; // global so we can remove them later
const typeSelect = document.getElementById('type');

function addInteractions() {
  draw = new Draw({
    source: source,
    type: typeSelect.value,
  });
  map.addInteraction(draw);
  snap = new Snap({source: source});
  map.addInteraction(snap);
}

/**
 * Handle change event.
 */
typeSelect.onchange = function () {
  map.removeInteraction(draw);
  map.removeInteraction(snap);
  addInteractions();
};

addInteractions();

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>Draw and Modify 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">Geometry type &nbsp;</label>
      <select id="type">
        <option value="Point">Point</option>
        <option value="LineString">LineString</option>
        <option value="Polygon">Polygon</option>
        <option value="Circle">Circle</option>
      </select>
    </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>