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JavaScript Object-Oriented JavaScript (2015) Prototypal Inheritance Setting Up the Prototype Chain

Ajay Yadav
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Ajay Yadav
Full Stack JavaScript Techdegree Graduate 18,261 Points
Posted by Ajay Yadav
.a{fill-rule:evenodd;}techdegree seal-36
Ajay Yadav
Full Stack JavaScript Techdegree Graduate 18,261 Points

where is the problem

Its not working. can you help me. how will it work?

person.js 
function Person(firstName, lastName) {
  this.firstName = firstName;
  this.lastName = lastName;
}

Person.prototype.fullName = function() {
 return this.firstName + " " + this.lastName; 
};
teacher.js 
function Teacher(firstName, lastName, roomNumber) {
    person.call(firstName, lastName,this);
  this.room = roomNumber;


}
Teacher.prototype=object.create(person.prototype);

1 Answer

Arpad Vas
Arpad Vas
11,823 Points
Arpad Vas
Arpad Vas
11,823 Points

This will work:

function Person(firstName, lastName) { this.firstName = firstName; this.lastName = lastName; }

Person.prototype.fullName = function() { return this.firstName + " " + this.lastName; };

var person1 = new Person("John", "Doe");

alert(person1.fullName());

function Teacher(firstName, lastName, roomNumber) { Person.call(this, firstName, lastName); this.room = roomNumber; }

Teacher.prototype = Object.create(Person.prototype);

var teacher1 = new Teacher("Jane", "Doe", 5);

alert(teacher1.fullName());

"this" comes in the first place inside the paranthesis. JS is case sensitive. Make sure if you use capital letter in the constructor then use it in the same way when referring it later.