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

Posted by dyon gerwen
dyon gerwen
2,963 Points

where does .fullName comes from ?? please help me

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

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

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

1 Answer

Ryan M
Ryan M
16,509 Points
Ryan M
Ryan M
16,509 Points

.fullName is a method on the Person object type from the Person.prototype.fullName declaration. Since the Teacher object type inherits from the Person object type, it also inherits this method.

teacher.js

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