Question

Example of using an ArcGIS REST Feature Service with a Tile strategy.

本示例演示，当 view 范围变化的时候，地图加载从 ArcGIS REST 服务获取的 feature 对象数据。

main.js

import 'ol/ol.css';
import EsriJSON from 'ol/format/EsriJSON';
import Map from 'ol/Map';
import VectorSource from 'ol/source/Vector';
import View from 'ol/View';
import XYZ from 'ol/source/XYZ';
import {Fill, Stroke, Style} from 'ol/style';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer';
import {createXYZ} from 'ol/tilegrid';
import {fromLonLat} from 'ol/proj';
import {tile as tileStrategy} from 'ol/loadingstrategy';

const serviceUrl =
  'https://sampleserver3.arcgisonline.com/ArcGIS/rest/services/' +
  'Petroleum/KSFields/FeatureServer/';
const layer = '0';

const esrijsonFormat = new EsriJSON();

const styleCache = {
  'ABANDONED': new Style({
    fill: new Fill({
      color: 'rgba(225, 225, 225, 255)',
    }),
    stroke: new Stroke({
      color: 'rgba(0, 0, 0, 255)',
      width: 0.4,
    }),
  }),
  'GAS': new Style({
    fill: new Fill({
      color: 'rgba(255, 0, 0, 255)',
    }),
    stroke: new Stroke({
      color: 'rgba(110, 110, 110, 255)',
      width: 0.4,
    }),
  }),
  'OIL': new Style({
    fill: new Fill({
      color: 'rgba(56, 168, 0, 255)',
    }),
    stroke: new Stroke({
      color: 'rgba(110, 110, 110, 255)',
      width: 0,
    }),
  }),
  'OILGAS': new Style({
    fill: new Fill({
      color: 'rgba(168, 112, 0, 255)',
    }),
    stroke: new Stroke({
      color: 'rgba(110, 110, 110, 255)',
      width: 0.4,
    }),
  }),
};

const vectorSource = new VectorSource({
  loader: function (extent, resolution, projection, success, failure) {
    const url =
      serviceUrl +
      layer +
      '/query/?f=json&' +
      'returnGeometry=true&spatialRel=esriSpatialRelIntersects&geometry=' +
      encodeURIComponent(
        '{"xmin":' +
          extent[0] +
          ',"ymin":' +
          extent[1] +
          ',"xmax":' +
          extent[2] +
          ',"ymax":' +
          extent[3] +
          ',"spatialReference":{"wkid":102100}}'
      ) +
      '&geometryType=esriGeometryEnvelope&inSR=102100&outFields=*' +
      '&outSR=102100';
    $.ajax({
      url: url,
      dataType: 'jsonp',
      success: function (response) {
        if (response.error) {
          alert(
            response.error.message + '\n' + response.error.details.join('\n')
          );
          failure();
        } else {
          // dataProjection will be read from document
          const features = esrijsonFormat.readFeatures(response, {
            featureProjection: projection,
          });
          if (features.length > 0) {
            vectorSource.addFeatures(features);
          }
          success(features);
        }
      },
      error: failure,
    });
  },
  strategy: tileStrategy(
    createXYZ({
      tileSize: 512,
    })
  ),
});

const vector = new VectorLayer({
  source: vectorSource,
  style: function (feature) {
    const classify = feature.get('activeprod');
    return styleCache[classify];
  },
});

const raster = new TileLayer({
  source: new XYZ({
    attributions:
      'Tiles © <a href="https://services.arcgisonline.com/ArcGIS/' +
      'rest/services/World_Topo_Map/MapServer">ArcGIS</a>',
    url:
      'https://server.arcgisonline.com/ArcGIS/rest/services/' +
      'World_Topo_Map/MapServer/tile/{z}/{y}/{x}',
  }),
});

const map = new Map({
  layers: [raster, vector],
  target: document.getElementById('map'),
  view: new View({
    center: fromLonLat([-97.6114, 38.8403]),
    zoom: 7,
  }),
});

const displayFeatureInfo = function (pixel) {
  const features = [];
  map.forEachFeatureAtPixel(pixel, function (feature) {
    features.push(feature);
  });
  if (features.length > 0) {
    const info = [];
    let i, ii;
    for (i = 0, ii = features.length; i < ii; ++i) {
      info.push(features[i].get('field_name'));
    }
    document.getElementById('info').innerHTML = info.join(', ') || '(unknown)';
    map.getTarget().style.cursor = 'pointer';
  } else {
    document.getElementById('info').innerHTML = '&nbsp;';
    map.getTarget().style.cursor = '';
  }
};

map.on('pointermove', function (evt) {
  if (evt.dragging) {
    return;
  }
  const pixel = map.getEventPixel(evt.originalEvent);
  displayFeatureInfo(pixel);
});

map.on('click', function (evt) {
  displayFeatureInfo(evt.pixel);
});

index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>ArcGIS REST Feature Service</title>
    <!-- Pointer events polyfill for old browsers, see https://caniuse.com/#feat=pointer -->
    <script src="https://unpkg.com/elm-pep"></script>
    <!-- The line below is only needed for old environments like Internet Explorer and Android 4.x -->
    <script src="https://cdn.polyfill.io/v3/polyfill.min.js?features=fetch,requestAnimationFrame,Element.prototype.classList,URL,TextDecoder,Number.isInteger"></script>
    <script src="./resources/jquery-3.5.1.min.js"></script>
    <style>
      .map {
        width: 100%;
        height:400px;
      }
    </style>
  </head>
  <body>
    <div id="map" class="map"></div>
    <div id="info">&nbsp;</div>
    <script src="main.js"></script>
  </body>
</html>

package.json

{
  "name": "vector-esri",
  "dependencies": {
    "ol": "7.1.0"
  },
  "devDependencies": {
    "parcel": "^2.0.0-beta.1"
  },
  "scripts": {
    "start": "parcel index.html",
    "build": "parcel build --public-url . index.html"
  }
}