如何在 JS 中從另一個 class 調用 static 方法

Question

我需要計算 3 個類（正方形、矩形、圓形）的面積，在class AreaCalculator中只有 1 個 static 方法。 我怎樣才能做到這一點？

  class Square {
  
  constructor(side) {
    this.sides = side;
  }
}

class Rectangle {
  constructor(width, height) {
    this.width = width;
    this.height = height;
  }
}

class Circle {

  constructor(radius) {
    this.radius = radius;
  }
}

class AreaCalculator {
  // ... static method to implement

}

const square = new Square(4);
const rectangle = new Rectangle(4, 2);
const circle = new Circle(5);

console.log(AreaCalculator.calculate(square));
console.log(AreaCalculator.calculate(rectangle));
console.log(AreaCalculator.calculate(circle));

Answer 1

像這樣的東西？

static calculate(shape) {
        switch (shape.constructor.name) {
            case "Square": return shape.sides * shape.sides;
            case "Circle": return Math.PI * shape.radius * shape.radius;
            case "Rectangle": return shape.width * shape.height;
        }
    }