javascript设计模式 - 多态

var makeSound = function(animal){if( animal instanceof Duck){console.log('嘎嘎嘎');}else if(animal inst

var makeSound = function(animal){if( animal instanceof Duck){console.log('嘎嘎嘎');}else if(animal instanceof Chicken){console.log('咯咯咯');}}; var Duck = function(){};var Chicken = function(){};makeSound(new Duck());  //嘎嘎嘎makeSound( new Chicken()); //咯咯咯

var makeSound = function(animal){animal.sound();}//然后把可变的部分各自封装起来var Duck = function(){}Duck.prototype.sound = function(){console.log('嘎嘎嘎');};var Chicken = function(){}Chicken.prototype.sound = function(){console.log('咯咯咯');};makeSound(new Duck());	//嘎嘎嘎makeSound(new  Chicken());		//咯咯咯