​x
 
<!DOCTYPE html>
<html>
<body>
​
<h3>如何访问 UL 元素的演示</h3>
​
<ul id="myUL">
  <li>Coffee</li>
  <li>Tea</li>
  <li>Milk</li>
</ul>
​
<p>点击按钮获取无序列表的id。</p>
​
<button onclick="myFunction()">试一试</button>
​
<p id="demo"></p>
​
<script>
function myFunction() {
  var x = document.getElementById("myUL").id;
  document.getElementById("demo").innerHTML = x;
}
</script>
​
</body>
</html>
​
​