javascript prototype throw the error as "Object [object Object] has no method"

Question

I am doing a prototype inheritance method test.. i am getting a error, even after i copied the instance to my existing object...

what is wrong here..

my test :

var human = function(name){
    this.name = name;
}

human.prototype.say = function(){
    alert(this.name);
}

var male = function(gender){
    this.gender = gender;
}

male.prototype.Gender = function(){
    alert(this.gender);
}

var inst1 = new human('nw louies');
inst1.say();

var inst2 = new male("male");
inst2.prototype = new human("sa loues philippe"); //i am copying the instance of human
inst2.Gender();
inst2.say(); // throw the error as "undefined"

what is wrong here.. any one help me to understand my mistake?

live demo here

Dennis · Accepted Answer · 2013-07-25 12:15:14Z

1

You need to say

var male = function(gender){
    this.gender = gender;
}

male.prototype = new human();

Don't forget that you also need to set the name property of male objects. You could expose a setName method on human and call that in the male constructor function, for example.

answered Jul 25, 2013 at 12:15

Dennis

14.5k3 gold badges37 silver badges56 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

3gwebtrain Over a year ago

can you please update my jsfiddle to get more understanding please?

Dennis Over a year ago

Have a look at this: jsfiddle.net/4WDxR/2 I hope it is of some help for your, feel free to ask otherwise

mohkhan · Accepted Answer · 2013-07-25 12:17:21Z

0

The prototype property is defined on constructors/functions only. So...

var obj = { a: 10 };
obj.prototype = { b : 20 }; // Wont't work

obj.constructor.prototype.say = function(){
    alert("Hello");
}

obj.say(); // Works.

I hope you understand

answered Jul 25, 2013 at 12:17

mohkhan

12.3k2 gold badges27 silver badges27 bronze badges

Collectives™ on Stack Overflow

javascript prototype throw the error as "Object [object Object] has no method"

2 Answers 2

2 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related