Inheritance

Inheritance is a fundamental concept in object-oriented programming,
It allows you to create new objects based on existing objects, thereby sharing and reusing code and behaviors.
In JavaScript, inheritance is achieved using prototypes and constructor functions or classes.

Example:

displays the year value from a given date

<!DOCTYPE html>
<html>

<body>

  <script>
    class Moment extends Date {
      constructor(year) {
        super(year);
      }
    }
    var m = new Moment("August 15, 1947 20:22:10");
    document.writeln("Year value:")
    document.writeln(m.getFullYear());
  </script>

</body>

</html>

Output:

Year value: 1947

Custom class:

We declare the subclass and it will extend the properties of its parent class.

Example:

<!DOCTYPE html>
<html>

<body>

  <script>
    class Bike {
      constructor() {
        this.company = "Honda";
      }
    }
    class Vehicle extends Bike {
      constructor(name, price) {
        super();
        this.name = name;
        this.price = price;
      }
    }
    var v = new Vehicle("Honda", "40000");
    document.writeln(v.company + " " + v.name + " " + v.price);
  </script>

</body>

</html>

Output:

Honda 40000