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Other References

CSSStyleDeclaration JS Conversion


JavaScript class Declaration


Example

Create a Car class, and then create an object called "mycar" based on the Car class:

class Car {  // Create a class
  constructor(brand) {  // Constructor
    this.carname = brand;  // Class body
  }
}
mycar = new Car("Ford");  // Create an object of Car class

Try it Yourself »


Definition and Usage

A class is a type of function, but instead of using the keyword function to initiate it, we use the keyword class, and the properties are assigned inside a constructor() method.

The constructor() method is called each time the class object is initialized.

Note: Unlike functions, and other JavaScript declarations, class declarations are not hoisted (you must declare a class before you can use it).

Note: The syntax in classes must be written in "strict mode".

For more information about classes, read our JavaScript Classes Tutorial.


Browser Support

The following table defines the first browser version with full support for Classes in JavaScript:

Keyword
class 49.0 12.0 45.0 9.0 36.0

Syntax

class className {
  // class body
}

Technical Details

JavaScript Version: ECMAScript 2015 (ES6)

Related Pages

JavaScript Tutorial: JavaScript Classes

JavaScript Tutorial: JavaScript ES6 (EcmaScript 2015)

JavaScript Tutorial: JavaScript this

JavaScript Tutorial: JavaScript Strict Mode