javascript 装饰者模式

```

//javascript 装饰者模式

//

function Sale(price) {

this.price = price || "100";

this.decorates_list = [];//要装饰的

}

Sale.prototype.getPrice = function () {

var price = this.price,

i,

name,

max = this.decorates_list.length;

for (i = 0; i < max; i++) {

name = this.decorates_list[i];

price = Sale.decorators[name].getPrice(price);

}

return price;

}

//装饰方法

//@parames decorator 装饰物名字

Sale.prototype.decorate = function (decorator) {

this.decorates_list.push(decorator);

}

Sale.decorators={};//装饰物集合

//装饰物，商品包邮

Sale.decorators.baoyou={

getPrice: function(price){

return price - 10;

}

}

//装饰物，商品打折

Sale.decorators.dazhe={

getPrice: function(price){

return price * 0.8;

}

}

//测试

var s = new Sale(99);

s.decorate("baoyou");

s.decorate("dazhe");

console.log(s.getPrice());

```