​x
 
<!DOCTYPE html>
<html>
<body>
​
<p>delete 运算符从对象中删除属性。</p>
​
<p id="demo"></p>
​
<script>
var person = {
  firstname:"Bill",
  lastname:"Gates",
  age:19,
  eyecolor:"blue"
};
delete person.age;
document.getElementById("demo").innerHTML =
person.firstname + " is " + person.age + " years old.";
</script>
​
</body>
</html>
​