JAVASCRIPT

what is the use of a constructor method in javascript

/* A constructor in Javascript is used to create a new object and set values
for any existing object properties*/

class Animal{
  
  constructor (name, height, weight){
    console.log("created animal named", name)
  }
  nameLength() {
    return name.length;
    
  }
  
}
 var dog = new Animal("Fido", 25, 90);
 var fish = new Animal("Goldie", 2, .02);

	console.log(dog.nameLength);

constructor function javascript

//Constructor Function
function BellBoy (name, age, hasWorkPermit, languages) {
  this.name = name;
  this.age = age;
  this.hasWorkPermit = hasWorkPermit;
  this.languages = languages;
}

//Create New Object From Constructor Using Arguments
var Earl = new BellBoy('Earl E.Bird', 23, true, ['French', 'German'])

//Access the Properties and Their Values
console.log('Name : ', Earl.name)
console.log('Age : ', Earl.age)
console.log('Verified Work Permit : ', Earl.hasWorkPermit)
console.log('Languages : ', Earl.languages)

constructor js

var MyConstructor = function(p1, p2, p3){
  this.p1 = p1;
  this.p2 = p2;
  this.p3 = p3;
};

What is constructor.constructor()() in JavaScript

const o = {};
o.constructor === Object;