Line Styles

<!--
  示例：线样式 — OpenLayers line-styles
  核心逻辑：同一条折线用多组 Stroke 参数绘制，比较宽度、端点、拐角、虚线样式
  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>线样式</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:16px;align-items:center;font-size:12px;color:#58606e;flex-wrap:wrap}
  #map{flex:1 1 auto;min-height:0;background:#eef0f3}
</style>
</head>
<body>
<div class="bar">
  <span>自上而下：宽度 1–7 px、round / miter 拐角、实线与虚线</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;
  }

  /* 七条水平折线，每条一种描边参数 */
  var specs = [
    { width: 1, color: '#1f5fd0', cap: 'butt', join: 'miter', dash: null, label: '1px butt miter' },
    { width: 2, color: '#1f5fd0', cap: 'round', join: 'round', dash: null, label: '2px round round' },
    { width: 4, color: '#c92a2a', cap: 'square', join: 'bevel', dash: null, label: '4px square bevel' },
    { width: 6, color: '#2f9e44', cap: 'round', join: 'miter', dash: [12, 6], label: '6px 虚线 12/6' },
    { width: 7, color: '#e8590c', cap: 'round', join: 'round', dash: [2, 8], label: '7px 点线 2/8' },
    { width: 5, color: '#7048e8', cap: 'butt', join: 'miter', dash: [20, 8, 4, 8], label: '5px 复合虚线' },
    { width: 3, color: '#0c8599', cap: 'round', join: 'round', dash: [18, 0], label: '3px 长划（虚线复位）' }
  ];

  var features = [];

  specs.forEach(function (spec, idx) {
    var lat = 39.945 - idx * 0.009;
    var coords = [
      [116.320, lat - 0.002],
      [116.360, lat + 0.003],
      [116.400, lat - 0.003],
      [116.440, lat + 0.003],
      [116.470, lat - 0.001]
    ].map(function (c) { return ol.proj.fromLonLat(c); });

    var feature = new ol.Feature({
      geometry: new ol.geom.LineString(coords),
      label: spec.label
    });

    feature.setStyle(new ol.style.Style({
      stroke: new ol.style.Stroke({
        color: spec.color,
        width: spec.width,
        lineCap: spec.cap,
        lineJoin: spec.join,
        lineDash: spec.dash || undefined
      }),
      text: new ol.style.Text({
        text: spec.label,
        placement: 'point',
        font: '500 11px sans-serif',
        offsetY: -10,
        fill: new ol.style.Fill({ color: '#16181d' }),
        stroke: new ol.style.Stroke({ color: '#fff', width: 3 })
      })
    }));

    features.push(feature);
  });

  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'}), opacity: 0.55 }),
      new ol.layer.Vector({ source: new ol.source.Vector({ features: features }) })
    ],
    view: new ol.View({
      center: ol.proj.fromLonLat([116.395, 39.915]),
      zoom: 12,
      minZoom: 2
    }),
    controls: ol.control.defaults.defaults({ attribution: false })
  });
})();
</script>
</body>
</html>