Class in JavaScript

Constructor Functions

Constructor Function:

A constructor function is a special type of function in JavaScript, which helps create new objects (data structures) with different prototypes.
It is an old syntax, used before the introduction of "class" syntax in JavaScript (ES6, 2016).
It also allows to add methods and properties in the prototype of the newly created object (data structure)
"Constructor function" and "function constructor" are completely different things,

function Person (person_name, person_age, person_gender) {
    this.name = person_name,
    this.age = person_age,
    this.gender = person_gender,
    this.greet = function () {
        return ('Hi' + ' ' + this.name);
    }
}

Person.prototype.getUserName = function(name){
  return this.name
}

const person1 = new Person('yash', 30, "Male")
person1

Classes in JavaScript

"Class"

In ES6, 2015, "class" was introduced as a new way for defining Objects, instead of "constructor functions",
To create a new class, we have the "class" keyword declaration with a name (starting with Uppercase)
We can also use the "class" expression to create a new class

class User {
  constructor(name) {
    this.name = name;
  }
  sayHi() {
    console.log(`Hi ${this.name}`);
  }
}

// Usage:
let user1 = new User("John");
user1.sayHi(); // Hi John

let user2 = new User("Doe");
user2.sayHi(); // Hi  Doe

Class in JavaScript

By Yash Priyam

Class in JavaScript

251

Yash Priyam