​x
 
<!DOCTYPE html>
<html>
<body>
​
<h1>Element 对象</h1>
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<h2>id 属性</h2>
​
<p><a id="myAnchor" href="https://www.w3school.com.cn/">W3School</a></p>
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<p>单击“更改”可更改链接的 id 属性的值。</p>
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<button onclick="changeID()">更改</button>
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<p>链接的 id 是：</p>
<p id="demo"></p>
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<script>
function getID() {
  document.getElementById("demo").innerHTML = element.id;
}
function changeID() {
  element.id = "newid";
  getID();   
}
​
let element = document.getElementById("myAnchor");
getID();
</script>
​
</body>
</html>
​