html运行实例（js_object_es5

代码示例：（标识：js_object_es5_4）

<!DOCTYPE html>
<html>
<body>

<h1>JavaScript Object.defineProperty()</h1>

<p>本例为对象添加一个新属性。</p>

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

<script>
// 创建对象：
const person = {
  firstName: "John",
  lastName: "Doe",
  language: "EN"
};

// 添加属性
Object.defineProperty(person, "year", {value:"2008"})
document.getElementById("demo").innerHTML = person.year;
</script>

</body>
</html>