Map Bounds Restriction

Sample code for Google Maps Platform JavaScript API author(s): Justin Poehnelt

HTML

<!doctype html>
<!--
 @license
 Copyright 2019 Google LLC. All Rights Reserved.
 SPDX-License-Identifier: Apache-2.0
-->
<html>
  <head>
    <title>Map Bounds Restriction</title>

    <!-- jsFiddle will insert css and js -->
  </head>
  <body>
    <div id="map"></div>

    <!-- 
      The `defer` attribute causes the script to execute after the full HTML
      document has been parsed. For non-blocking uses, avoiding race conditions,
      and consistent behavior across browsers, consider loading using Promises. See
      https://developers.google.com/maps/documentation/javascript/load-maps-js-api
      for more information.
      -->
    <script
      src="https://maps.googleapis.com/maps/api/js?key=AIzaSyB41DRUbKWJHPxaFjMAwdrzWzbVKartNGg&callback=initMap&v=weekly"
      defer
    ></script>
  </body>
</html>

CSS

/**
 * @license
 * Copyright 2019 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */
/* 
 * Always set the map height explicitly to define the size of the div element
 * that contains the map. 
 */
#map {
  height: 100%;
}

/* 
 * Optional: Makes the sample page fill the window. 
 */
html,
body {
  height: 100%;
  margin: 0;
  padding: 0;
}

JavaScript

/**
 * @license
 * Copyright 2019 Google LLC. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */
let map;
const NEW_ZEALAND_BOUNDS = {
  north: -34.36,
  south: -47.35,
  west: 166.28,
  east: -175.81,
};
const AUCKLAND = { lat: -37.06, lng: 174.58 };

function initMap() {
  map = new google.maps.Map(document.getElementById("map"), {
    center: AUCKLAND,
    restriction: {
      latLngBounds: NEW_ZEALAND_BOUNDS,
      strictBounds: false,
    },
    zoom: 7,
  });
}

window.initMap = initMap;