库

如需加载 Maps JavaScript API 的 JavaScript 代码，您需要在网页上添加引导程序加载器脚本，格式如下：

<script>
  (g=>{var h,a,k,p="The Google Maps JavaScript API",c="google",l="importLibrary",q="__ib__",m=document,b=window;b=b[c]||(b[c]={});var d=b.maps||(b.maps={}),r=new Set,e=new URLSearchParams,u=()=>h||(h=new Promise(async(f,n)=>{await (a=m.createElement("script"));e.set("libraries",[...r]+"");for(k in g)e.set(k.replace(/[A-Z]/g,t=>"_"+t[0].toLowerCase()),g[k]);e.set("callback",c+".maps."+q);a.src=`https://maps.${c}apis.com/maps/api/js?`+e;d[q]=f;a.onerror=()=>h=n(Error(p+" could not load."));a.nonce=m.querySelector("script[nonce]")?.nonce||"";m.head.append(a)}));d[l]?console.warn(p+" only loads once. Ignoring:",g):d[l]=(f,...n)=>r.add(f)&&u().then(()=>d[l](f,...n))})({
    key: "YOUR_API_KEY",
    v: "weekly",
    // Use the 'v' parameter to indicate the version to use (weekly, beta, alpha, etc.).
    // Add other bootstrap parameters as needed, using camel case.
  });
</script>

Maps JavaScript API 由多个库组成，这些库在您明确请求之前不会加载。将组件分散到各个库中，可使该 API 快速加载（和解析）。这样，只有在需要加载和解析库时，才会产生额外的开销。

在运行时加载其他库，方法是使用 await 运算符在 async 函数中调用 importLibrary()。例如：

const { Map } = await google.maps.importLibrary("maps");

以下代码示例展示了如何同时加载 Map 和 AdvancedMarkerElement 库：

TypeScript

// Initialize and add the map
let map;
async function initMap(): Promise<void> {
  // The location of Uluru
  const position = { lat: -25.344, lng: 131.031 };

  // Request needed libraries.
  //@ts-ignore
  const { Map } = await google.maps.importLibrary("maps") as google.maps.MapsLibrary;
  const { AdvancedMarkerElement } = await google.maps.importLibrary("marker") as google.maps.MarkerLibrary;

  // The map, centered at Uluru
  map = new Map(
    document.getElementById('map') as HTMLElement,
    {
      zoom: 4,
      center: position,
      mapId: 'DEMO_MAP_ID',
    }
  );

  // The marker, positioned at Uluru
  const marker = new AdvancedMarkerElement({
    map: map,
    position: position,
    title: 'Uluru'
  });
}

initMap();
index.ts

JavaScript

// Initialize and add the map
let map;

async function initMap() {
  // The location of Uluru
  const position = { lat: -25.344, lng: 131.031 };
  // Request needed libraries.
  //@ts-ignore
  const { Map } = await google.maps.importLibrary("maps");
  const { AdvancedMarkerElement } = await google.maps.importLibrary("marker");

  // The map, centered at Uluru
  map = new Map(document.getElementById("map"), {
    zoom: 4,
    center: position,
    mapId: "DEMO_MAP_ID",
  });

  // The marker, positioned at Uluru
  const marker = new AdvancedMarkerElement({
    map: map,
    position: position,
    title: "Uluru",
  });
}

initMap();
index.js

可用的库

以下库可与动态库导入和直接脚本加载标记搭配使用：

以下引导加载程序请求展示了如何将对 Maps JavaScript API 的 google.maps.geometry 库的请求添加到直接脚本加载标记中：

<script async
    src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&loading=async&libraries=geometry&callback=initMap">
</script>

若要请求多个库，请用英文逗号分隔：

<script async
    src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&loading=async&libraries=geometry,places&callback=initMap">
</script>