How do I inherit properties using prototypes in JavaScript?

How do I inherit properties using prototypes in JavaScript?

In JavaScript, you can inherit properties using prototypes by setting the prototype of one constructor function to another. For example, if you have a parent constructor Animal and a child constructor Dog, you can set Dog.prototype = Object.create(Animal.prototype);.

Can you give me an example of how that works?

Sure! Here's a simple example:

function Animal(name) {
    this.name = name;
}

Animal.prototype.speak = function() {
    console.log(`${this.name} makes a noise.`);
};

function Dog(name) {
    Animal.call(this, name);
}

Dog.prototype = Object.create(Animal.prototype);
Dog.prototype.bark = function() {
    console.log(`${this.name} barks.`);
};

const dog = new Dog('Rex');

dog.speak(); // Rex makes a noise.
dog.bark();  // Rex barks.

What if I want to add more properties to the Dog class?

You can add more properties directly in the Dog constructor. For example:

function Dog(name, breed) {
    Animal.call(this, name);
    this.breed = breed;
}

Now, each Dog instance will have both name and breed properties.

Thanks! This really helps clarify how prototypes work.