装饰模式-JS

• 咖啡

咖啡

咖啡添加配料。

class SimpleCoffee {
  getCost() {
    return 10;
  }

  getDescription() {
    return 'Simple Coffee';
  }
}

class MilkCoffee {
  constructor(coffee) {
    this.coffee = coffee;
  }

  getCost() {
    return this.coffee.getCost() + 2;
  }

  getDescription() {
    return this.coffee.getDescription() + ', milk';
  }
}

class WhipCoffee {
  constructor(coffee) {
    this.coffee = coffee;
  }

  getCost() {
    return this.coffee.getCost() + 5;
  }

  getDescription() {
    return this.coffee.getDescription() + ', whip';
  }
}

class VanillaCoffee {
  constructor(coffee) {
    this.coffee = coffee;
  }

  getCost() {
    return this.coffee.getCost() + 3;
  }

  getDescription() {
    return this.coffee.getDescription() + ', vanilla';
  }
}

// client
let someCoffee;

someCoffee = new SimpleCoffee();
console.log(someCoffee.getCost()); // 10
console.log(someCoffee.getDescription()); // Simple Coffee

someCoffee = new MilkCoffee(someCoffee);
console.log(someCoffee.getCost()); // 12
console.log(someCoffee.getDescription()); // Simple Coffee, milk

someCoffee = new WhipCoffee(someCoffee);
console.log(someCoffee.getCost()); // 17
console.log(someCoffee.getDescription()); // Simple Coffee, milk, whip

someCoffee = new VanillaCoffee(someCoffee);
console.log(someCoffee.getCost()); // 20
console.log(someCoffee.getDescription()); // Simple Coffee, milk, whip, vanilla