代码示例：（标识：js_api_geolocation_watchposition）
<!DOCTYPE html>
<html>
<body>
<h1>JavaScript Geolocation API</h1>
<p>单击按钮以获取您的坐标。</p>
<button onclick="getLocation()">试一试</button>
<p id="demo"></p>
<script>
const x = document.getElementById("demo");
function getLocation() {
if (navigator.geolocation) {
navigator.geolocation.watchPosition(showPosition);
} else {
x.innerHTML = "Geolocation is not supported by this browser.";
}
}
function showPosition(position) {
x.innerHTML="Latitude: " + position.coords.latitude +
"<br>Longitude: " + position.coords.longitude;
}
</script>
</body>
</html>
