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