JavaScript 构建类和创建对象的方式

1>工厂函数来创建对象(Factory)

     function createCar(){ var obj = new Object; obj.name = "BWM"; obj.show = function(){ alert(this.name); } return obj;}var car1 = createCar();var car2 = createCar();car1.show();car2.show();

2>构造函数创建对象(Constructor)

     function Car(name){ this.name = name; this.show = function(){ alert(this.name); }}Car.prototype.say = function(){ alert("hello");}var car = new Car("BMW");car.show();car.say();

3>原型（prototype）创建对象

      function Car(){}Car.prototype.name = "BMW";Car.prototype.show = function(){ alert(this.name);}Car.prototype.say = function(){ alert("Hiloo");}var car = new Car();car.show(); car.say();

4>构造 && 原型：推荐使用，但是理解起来有点模糊

     /* 构造函数是来初始化非函数属性的*/function Car(name){ this.name = name;}Car.prototype.show = function(){ alert(this.name);}Car.prototype.say = function(){ alert("hiloo");}var car = new Car("BMW");car.show(); car.say();

5>Dynamic Prototype：类似于java中类的创建，是学习过Java语言程序员常用的方式

    function Car(name){ this.name = name; if(typeof Car._initialized == "undefined"){ Car.prototype.show = function(){ alert(this.name); } Car._initialized = true;//改变目的是，执行一次 }}var car = new Car("BMW");car.show();