constructor in javascipt code example

Example 1: constructor in js

A constructor is a function that creates an instance of a class
  which is typically called an “object”. In JavaScript, a constructor gets 
  called when you declare an object using the new keyword.
  The purpose of a constructor is to create an object and set values if 
  there are any object properties present.

Example 2: javascript class constructor

class Cat {
        constructor(name, age) {
            this.name = name;
            this.age = age;
        }
      
      	get fullname() {
          return this.getFullName()
        }
        getFullName() {
            return this.name + ' ' + this.age
        }
    }

    const run = document.getElementById("run");
    run.addEventListener("click", function () {
        let Skitty = new Cat('Skitty', 9);
        let Pixel = new Cat('Pixel', 6);
        console.log(Skitty.getFullName()); // Skitty 9
      	console.log(Skitty.fullname); // Skitty 9 => shorter syntax
        console.log(Skitty, Pixel); 
      // Object { name: "Skitty", age: 9} Object {name: "Pixel", age:6}
    })