javascript built in constructor functions code example

Example 1: javascript constructor function

function ClassMates(name,age){
  this.name=name;
  this.age=age;
  this.displayInfo=function(){
    return this.name + "is " + this.age + "year's old!";
  }
}

let classmate1 = new ClassMates("Mike Will", 15);
classmate.displayInfo(); // "Mike Will is 15 year's old!"

Example 2: how to create a constructor in javascript

function Bird() {
  this.name = "Albert";
  this.color  = "blue";
  this.numLegs = 2;
}

let blueBird = new Bird();