Edit Geographic

<!--
  说明：地理坐标编辑
  核心逻辑：Draw / Modify 编辑多边形，toLonLat 把顶点转成经纬度输出到面板
  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>地理坐标编辑</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:8px;align-items:center;font-size:12px;color:#58606e;flex-wrap:wrap}
  .bar button{font:inherit;padding:4px 10px;border:1px solid #c9d0da;border-radius:5px;
              background:#fff;color:#1f2a37;cursor:pointer}
  .bar button.on{background:#1f5fd0;border-color:#1f5fd0;color:#fff}
  .main{flex:1 1 auto;min-height:0;display:flex}
  #map{flex:1 1 auto;min-width:0;background:#eef0f3}
  #panel{flex:0 0 250px;border-left:1px solid #e3e6ea;background:#fbfcfd;
         padding:10px 12px;overflow:auto;font-size:12px}
  #panel h3{margin:0 0 8px;font-size:12px;color:#1f2a37}
  #panel ol{margin:0;padding-left:20px;font-family:Consolas,Menlo,monospace;color:#58606e}
  #panel li{margin:2px 0}
</style>
</head>
<body>
<div class="bar">
  <button id="btnDraw" class="on">绘制多边形</button>
  <button id="btnModify">修改</button>
  <button id="clear">清空</button>
  <span id="info">—</span>
</div>
<div class="main">
  <div id="map"></div>
  <div id="panel">
    <h3>顶点（经度, 纬度）</h3>
    <ol id="verts"><li>尚未绘制</li></ol>
  </div>
</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 fromLonLat = ol.proj.fromLonLat;

  var source = new ol.source.Vector();

  var layer = new ol.layer.Vector({
    source: source,
    style: new ol.style.Style({
      fill: new ol.style.Fill({ color: 'rgba(31,95,208,0.14)' }),
      stroke: new ol.style.Stroke({ color: '#1f5fd0', width: 2.5 }),
      image: new ol.style.Circle({
        radius: 5,
        fill: new ol.style.Fill({ color: '#ffffff' }),
        stroke: new ol.style.Stroke({ color: '#1f5fd0', width: 2 })
      })
    })
  });

  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'}) }), layer],
    view: new ol.View({ center: fromLonLat([116.391, 39.907]), zoom: 12, minZoom: 2, maxZoom: 19 }),
    controls: ol.control.defaults.defaults({ attribution: false, rotate: false })
  });

  var draw = new ol.interaction.Draw({ source: source, type: 'Polygon' });
  var modify = new ol.interaction.Modify({ source: source });
  modify.setActive(false);
  map.addInteraction(draw);
  map.addInteraction(modify);

  var verts = document.getElementById('verts');
  var info = document.getElementById('info');

  function refresh() {
    var list = [];
    source.getFeatures().forEach(function (f) {
      var geom = f.getGeometry();
      var ring = geom instanceof ol.geom.Polygon
        ? geom.getCoordinates()[0] : geom.getCoordinates();
      ring.forEach(function (c) {
        var ll = ol.proj.toLonLat(c);
        list.push(ll[0].toFixed(6) + ', ' + ll[1].toFixed(6));
      });
    });

    verts.innerHTML = '';
    if (!list.length) {
      verts.innerHTML = '<li>尚未绘制</li>';
    } else {
      list.forEach(function (txt) {
        var li = document.createElement('li');
        li.textContent = txt;
        verts.appendChild(li);
      });
    }
    info.textContent = list.length ? list.length + ' 个顶点' : '等待绘制';
  }

  draw.on('drawend', function () { setTimeout(refresh, 0); });
  modify.on('modifyend', refresh);

  document.getElementById('btnDraw').addEventListener('click', function () {
    draw.setActive(true);
    modify.setActive(false);
    this.classList.add('on');
    document.getElementById('btnModify').classList.remove('on');
    info.textContent = '绘制模式：双击结束';
  });

  document.getElementById('btnModify').addEventListener('click', function () {
    draw.setActive(false);
    modify.setActive(true);
    this.classList.add('on');
    document.getElementById('btnDraw').classList.remove('on');
    info.textContent = '修改模式：拖动折点';
  });

  document.getElementById('clear').addEventListener('click', function () {
    source.clear();
    refresh();
  });

  refresh();
})();
</script>
</body>
</html>