代码示例:(标识:eg_js_object_method_add)
<!DOCTYPE html>
<html>
<body>

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

<script>
var person = {
  firstName: "Bill",
  lastName : "Gates",
  id     : 678,
};
person.name = function() {
  return this.firstName + " " + this.lastName;
};

document.getElementById("demo").innerHTML =
"My friend is " + person.name(); 
</script>

</body>
</html>
运行结果: