How do you declare a class named 'Car' in JavaScript?

Understanding Class Declarations in JavaScript

JavaScript uses prototype-based inheritance and does not traditionally use classes like many object-oriented languages. However, with the introduction of ES6, also known as ES2015, we're now able to declare classes in JavaScript.

The correct way to declare a class named 'Car' in JavaScript is by using the class keyword followed by the name of the class as shown in the answer class Car {}.

Syntax for Class Declarations

A basic class declaration in JavaScript has the following syntax:

class ClassName {
  // class body

In the case of our 'Car' class, it would be declared as:

class Car {
  // class body

Practical Example

Let's assume our 'Car' class has properties like brand, model, and color. We want these properties to be customizable for every car object we create.

We can include a method in our 'Car' class, known as a constructor, to set these values while creating a new car object.

Here's what our 'Car' class would look like with a constructor:

class Car {
  constructor(brand, model, color) {
    this.brand = brand;
    this.model = model;
    this.color = color;

We can then create a new car object as follows:

let myCar = new Car('Toyota', 'Corolla', 'Blue');

When logging myCar in the console, you would get the object:

{ brand: 'Toyota', model: 'Corolla', color: 'Blue' }

Best Practices and Insights

When using class declarations, here are some best practices to follow:

  1. Use PascalCase for class names. While this is not enforced by the JavaScript language, it is a widely accepted industry standard.
  2. Always declare class methods without the function keyword. Again, this is a requirement imposed by the language.
  3. In a class, you use this to access properties that belong to the class.

Remember, even though ES6 introduced a class keyword, JavaScript is still a prototype-based language. Under the hood, this "class" is a syntactical sugar over JavaScript's existing prototype-based inheritance. The class syntax does not introduce a new object-oriented inheritance model to JavaScript.

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