JavaScript Reflect.setPrototypeOf() Method

The static Reflect.setPrototypeOf() method is used to set the prototype of a specified object to another object. The first argument is the object reference and the second argument can be either null or an object. This method is same as Object.setPrototypeOf() method.

Syntax:

Parameters:

Obj: It is the target object of which to set the prototype.

Prototype: It is the object's new prototype.

Return value:

This method returns a Boolean which indicates whether or not the prototype was successfully set.

Exceptions:

A TypeError, if the target is not an Object

Browser Support:

Chrome	49
Edge	12
Firefox	42
Opera	36

Example 1

const object = {};
console.log(Reflect.setPrototypeOf(Object.freeze(object), null));

Output:

False

Example 2

var Animal = {
   speak() {
     console.log(this.name + ' makes a noise.');
   }
};
class g {
   constructor(name) {
   this.name = name;
  }
}
Reflect.setPrototypeOf(g.prototype, Animal);
// If you do not do this you will get a TypeError when you invoke speak
var d = new g('Mitzie');
d.speak();

Output:

"Mitzie makes a noise."

Example 3

let toyota = {
  drive() {
    return 'value';
  }
}
let obj = {
  wifi() {
    return 'answer';
  }
}
Object.setPrototypeOf(obj, toyota);
console.dir(obj); 
document.write(obj.wifi());
document.writeln("<br/>");
document.writeln(obj.drive());

Output: