JavaScript Object.getPrototypeOf() 方法

JavaScript的object. getprototypeof()方法返回指定对象的原型(即内部[[prototype]]属性的值)。

语法:

Object.getPrototypeOf(obj) 

参数

obj:它是一个将被返回原型的对象。

返回值

这个方法返回给定对象的原型。如果没有继承属性，这个方法将返回null。

浏览器支持

Chrome	5
Edge	Yes
Firefox	3.5
Opera	12.1

示例1

let animal = {  
  eats: true  
};  
   // create a new object with animal as a prototype  
let rabbit = Object.create(animal);  
alert(Object.getPrototypeOf(rabbit) === animal); // get the prototype of rabbit  

Object.setPrototypeOf(rabbit, {}); // change the prototype of rabbit to {}  

输出:

true

示例2

const prototype1 = {};  
const object1 = Object.create(prototype1);  
const prototype2 = {};  
const object2 = Object.create(prototype2);  
console.log(Object.getPrototypeOf(object1) === prototype1);  
console.log(Object.getPrototypeOf(object1) === prototype2);   

输出:

true
false

示例3

const prototype1 = {};  
const object1 = Object.create(prototype1);  
const prototype2 = {};  
const object2 = Object.create(prototype2);  
console.log(Object.getPrototypeOf(object1) === prototype1);  
console.log(Object.getPrototypeOf(object2) === prototype2);   

输出:

true
true