​x
 
<!DOCTYPE html>
<html>
<body>
​
<h1>JavaScript defineProperty()</h1>
​
<p id="demo"></p>
​
<script>
// 创建对象：
var person = {
  firstName: "Bill",
  lastName : "Gates",
?? language : "NO", 
};
// 更改属性：
Object.defineProperty(person, "language", {
  value: "EN",
  writable : true,
  enumerable : false,
  configurable : true
});
// 枚举属性：
txt = "";
for (var x in person) {
  txt += person[x] + "<br>";
}
document.getElementById("demo").innerHTML = txt;
</script>
​
</body>
</html>
​