class inheritance javascript code example

Example 1: javascript class inheritance

// Class Inheritance in JavaScript
class Mammal {
	constructor(name) {
		this.name = name;
	}
	eats() {
		return `${this.name} eats Food`;
	}
}

class Dog extends Mammal {
	constructor(name, owner) {
		super(name);
		this.owner = owner;
	}
	eats() {
		return `${this.name} eats Chicken`;
	}
}

let myDog = new Dog("Spot", "John");
console.log(myDog.eats()); // Spot eats chicken

Example 2: override function javascript class

class newArray extends Array{
    push(value) {
        //execute any logic require before pushing value onto array
        console.log(`pushed ${value} on to array`)
        super.push(value)
    }    
}

var array = new newArray

array.push('new Value')

Example 3: javascript inherit function

function inherit(c, p) {
        Object.defineProperty(c, 'prototype', {
            value: Object.assign(c.prototype, p.prototype),
            writable: true,
            enumerable: false
        });

        Object.defineProperty(c.prototype, 'constructor', {
            value: c,
            writable: true,
            enumerable: false
        });
    }
// Or if you want multiple inheritance

function _inherit(c, ...p) {
        p.forEach(item => {
            Object.defineProperty(c, 'prototype', {
                value: Object.assign(c.prototype, item.prototype),
                writable: true,
                enumerable: false
            });
        })

        Object.defineProperty(c.prototype, 'constructor', {
            value: c,
            writable: true,
            enumerable: false
        });
    }