Class Fields and Methods

 Class Fields and Methods

Class fields and methods provide a more convenient way to define instance variables and methods directly within the class declaration.

class Circle {

  radius = 0;

  constructor(radius) {

    this.radius = radius;

  }

  get area() {

    return Math.PI * this.radius ** 2;

  }

  static circumference(radius) {

    return 2 * Math.PI * radius;

  }

}

const circle = new Circle(5);

console.log(circle.area); // Output: 78.53981633974483

console.log(Circle.circumference(5)); // Output: 31.41592653589793

In the example above, the Circle class has a class field radius and a getter method area that calculates the area of the circle. The circumference method is declared as a static method, which can be invoked directly on the class itself.