<h3>演示如何访问 SCRIPT 元素</h3>
<script id="myScript" src="/example/hdom/demo_script_src.js"></script>
<p>点击按钮来获得外部脚本文件的 URL。</p>
<button onclick="myFunction()">试一下</button>
var x = document.getElementById("myScript").src;
document.getElementById("demo").innerHTML = x;