JavaScript Class super
Description
The super keyword is used to call the constructor of its parent class
to access the parent's properties and methods.
Tip: To understand the "inheritance" concept (parent and child classes) better, read our JavaScript Classes Tutorial.
Example
Create a class named "Model" which will inherit the methods from the "Car"
class, by using the extends keyword.
By calling the super() method in the constructor method, we call the
parent's constructor method and gets access to the parent's properties and
methods:
class Car {
constructor(brand) {
this.carname =
brand;
}
present() {
return 'I have a ' + this.carname;
}
}
class Model extends Car {
constructor(brand, mod) {
super(brand);
this.model = mod;
}
show() {
return this.present() + ', it is a ' + this.model;
}
}
mycar = new Model("Ford", "Mustang");
document.getElementById("demo").innerHTML
= mycar.show();
Browser Support
super is an ECMAScript6 (ES6) feature.
ES6 (JavaScript 2015) is supported in all modern browsers since June 2017:
| Chrome 51 | Edge 15 | Firefox 54 | Safari 10 | Opera 38 |
| May 2016 | Apr 2017 | Jun 2017 | Sep 2016 | Jun 2016 |
super is not supported in Internet Explorer.
Syntax
super(arguments); // calls the parent constructor (only inside
the constructor)
super.parentMethod(arguments); // calls a parent method
Technical Details
| JavaScript Version: | ECMAScript 2015 (ES6) |
|---|
Related Pages
JavaScript Tutorial: JavaScript Classes
JavaScript Tutorial: JavaScript ES6 (EcmaScript 2015)
JavaScript Reference: The extends Keyword
JavaScript Reference: The constructor() method
