Graticule

<!--
  示例：经纬网格
  要点：ol.layer.Graticule 按缩放自动计算间隔，支持显示经纬度标签
  依赖：OpenLayers 10.3.1 · jsDelivr CDN
-->
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta name="robots" content="noindex,follow">
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>经纬网格</title>
<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/ol@10.3.1/ol.css">
<style>
  html,body{height:100%;margin:0}
  body{display:flex;flex-direction:column;overflow:hidden;
       font:13px/1.6 -apple-system,"Segoe UI","PingFang SC",sans-serif}
  .bar{flex:0 0 auto;padding:8px 12px;background:#f6f7f9;border-bottom:1px solid #e3e6ea;
       display:flex;gap:14px;align-items:center;font-size:12px;color:#58606e;flex-wrap:wrap}
  .bar label{display:flex;gap:5px;align-items:center;cursor:pointer}
  #map{flex:1 1 auto;min-height:0;background:#eef0f3}
</style>
</head>
<body>
<div class="bar">
  <label><input type="checkbox" id="tglGrid" checked> 显示经纬网格</label>
  <span>缩放级别变化后，网格间隔会自动调整</span>
</div>
<div id="map"></div>
<script src="https://cdn.jsdelivr.net/npm/ol@10.3.1/dist/ol.js"></script>
<script>
(function () {
  'use strict';

  if (typeof ol === 'undefined') {
    document.getElementById('map').innerHTML =
      '<div style="padding:20px;color:#b42318">OpenLayers 加载失败，请检查能否访问 cdn.jsdelivr.net</div>';
    return;
  }

  var graticule = new ol.layer.Graticule({
    strokeStyle: new ol.style.Stroke({
      color: 'rgba(31,95,208,0.55)',
      width: 1,
      lineDash: [4, 4]
    }),
    showLabels: true,
    wrapX: false,
    targetSize: 180
  });

  var map = new ol.Map({
    target: 'map',
    layers: [
      new ol.layer.Tile({ source: new ol.source.XYZ({url: 'https://server.arcgisonline.com/ArcGIS/rest/services/World_Street_Map/MapServer/tile/{z}/{y}/{x}', attributions: 'Tiles © Esri'}) }),
      graticule
    ],
    view: new ol.View({
      center: ol.proj.fromLonLat([105, 35]),
      zoom: 3,
      minZoom: 2,
      maxZoom: 8
    }),
    controls: ol.control.defaults.defaults({
      attribution: false,
      rotate: false
    })
  });

  document.getElementById('tglGrid').addEventListener('change', function () {
    graticule.setVisible(this.checked);
  });
})();
</script>
</body>
</html>