Adding prototype to an object is giving error

Question

I am trying to add prototype to already created object Instance (Person1) in this example, but it is not getting successfully added, and thereby giving error. Can someone help me out?

<html> 
<head></head>
<body>

<script>

var person = function(name, age){
this.name = name;
this.age = age; 
this.printName = function(){
    alert(this.name);
}
}
person.prototype.printAge = function(){
alert(this.age);
}

var person1 = new person("Jack", 29); 
person1.prototype.printMessage = function(){
alert("Hello Friend"); 
}

var person2 = object.create(person1);
person2.printName();
person2.printAge();
person2.printMessage();

</script>

</body>
</html>

Cause `object` is not `Object` – Jonas Wilms Mar 14 '18 at 06:42 — Jonas Wilms, Mar 14 '18 at 06:42

wisn · Answer 1 · 2018-03-14T06:50:32.567

1

The problem is that person is a function and person1 is an object. Use constructor.prototype to solve the problem.

<html> 
<head></head>
<body>

<script>

var person = function(name, age){
this.name = name;
this.age = age; 
this.printName = function(){
    alert(this.name);
}
}
person.prototype.printAge = function(){
alert(this.age);
}

var person1 = new person("Jack", 29); 
person1.constructor.prototype.printMessage = function(){
alert("Hello Friend"); 
}

var person2 = Object.create(person1);
person2.printName();
person2.printAge();
person2.printMessage();

</script>

</body>
</html>

edited Mar 14 '18 at 06:50

answered Mar 14 '18 at 06:43

wisn

974
10
17

`__proto__` is not a feature. – Jonas Wilms Mar 14 '18 at 06:45
@JonasW. Edited. – wisn Mar 14 '18 at 06:50

score 0 · Answer 2 · answered Mar 14 '18 at 06:46

0

Only constructor functions have protoype property (functions which sets the property values via this.propertyName. Although you can use

__proto__

it is deemed inefficient.

Check this.

stackoverflow reference

answered Mar 14 '18 at 06:46

Abinash Gupta

321
3
12

Adding prototype to an object is giving error

2 Answers2