constructor in js

1function ClassMates(name,age){
2  this.name=name;
3  this.age=age;
4  this.displayInfo=function(){
5    return this.name + "is " + this.age + "year's old!";
6  }
7}
8
9let classmate1 = new ClassMates("Mike Will", 15);
10classmate.displayInfo(); // "Mike Will is 15 year's old!"

1class Person {
2  constructor(name) {
3    this.name = name;
4  }
5  introduce() {
6    console.log(`Hello, my name is ${this.name}`);
7  }
8}

1A constructor is a function that creates an instance of a class
2  which is typically called an “object”. In JavaScript, a constructor gets 
3  called when you declare an object using the new keyword.
4  The purpose of a constructor is to create an object and set values if 
5  there are any object properties present.
6

1function Person(first, last, age, eye) {
2  this.firstName = first;
3  this.lastName = last;
4  this.age = age;
5  this.eyeColor = eye;
6}

1function Car(make, model, year) {
2  this.make = make;
3  this.model = model;
4  this.year = year;
5}
6
7var car1 = new Car('Eagle', 'Talon TSi', 1993);
8
9console.log(car1.make);
10// expected output: "Eagle"

1function Bird() {
2  this.name = "Albert";
3  this.color = "blue";
4  this.numLegs = 2;
5}
6/*
7This constructor defines a Bird object with properties name, color, and
8numLegs set to Albert, blue, and 2, respectively.
9Constructors follow a few conventions:
10-Constructors are defined with a capitalized name to distinguish them from
11other functions that are not constructors.
12
13-Constructors use the keyword this to set properties of the object they will
14create. Inside the constructor, this refers to the new object it will create.
15
16-Constructors define properties and behaviors instead of returning a value as
17other functions might.
18*/