js模式之策略模式

//普通用户
function Price(){
    this.discount = 1
}
Price.prototype.getPrice = function(price){
    return price * this.discount
}
//vip用户
function VipPrice(){
    this.discount = 0.5
}
VipPrice.prototype.getPrice = function(price){
    return price * this.discount
}
//超级VIP用户
function SuperVipPrice(){
    this.discount = 0.3
}
SuperVipPrice.prototype.getPrice = function(price){
    return price * this.discount
}

//上下文
function Context(){
    this.name="";
    this.strategy=null;
    this.price=0
}
Context.prototype.set=function(name,strategy,price){
    this.name=name;
    this.strategy=strategy;
    this.price=price;
}
Context.prototype.getResult=function(){
    console.log(this.name+"的价格是:"+this.strategy.getPrice(this.price))
}
let context = new Context();
let price = new Price();
context.set("普通用户",price,200);
context.getResult();
let vipPrice = new VipPrice();
context.set("vip用户",vipPrice,200);
context.getResult();
let superVipPrice = new SuperVipPrice();
context.set("超级vip用户",superVipPrice,200);
context.getResult();