html运行实例（jsck_document_implementation

代码示例：（标识：jsck_document_implementation_2）

<!DOCTYPE html>
<html>
<body>

<h1>Document 对象</h1>

<h2>implementation 属性</h2>

<p>此文档是否具有 Tesla X 特征？</p>

<p id="demo"></p>

<script>
let answer = document.implementation.hasFeature("TESLA", "X");
document.getElementById("demo").innerHTML = answer;
</script>

</body>
</html>