x
 
<!DOCTYPE html>
<html>
<body>
<p>单击该按钮可显示 UTC 与本地时间之间的时差。</p>
<button onclick="myFunction()">试一试</button>
<p id="demo"></p>
<script>
function myFunction() {
  var d = new Date();
  var n = d.getTimezoneOffset();
  document.getElementById("demo").innerHTML = n;
}
</script>
</body>
</html>