Javascript进阶(5)---编写类

/*使用写法①定义一个Pet类*/
function Pet(_name, _age, _price, _color)
{
    this.init(_name, _age, _price, _color);
}

Pet.prototype.name;
Pet.prototype.age;
Pet.prototype.price;
Pet.prototype.color;
Pet.prototype.init = function (_name, _age, _price, _color) 
{
    if (_name != undefined && _age != undefined && _price != undefined && _color != undefined)
    {
        this.name = _name;
        this.age = _age;
        this.price = _price;
        this.color = _color;
        document.writeln("this.name=" + this.name + ",this.age=" + this.age + ",this.price=" + this.price + ",this.color=" + this.color);
    }
}

function Person2() { } 
/*在类的prototype上以JS对象的形式构造一个类*/
Person2.prototype = 
{
    name : "", //public属性
    age : 0, weight : 0, height : 0, /*public方法*/
    init : function (_name, _age, _weight, _height) 
    {
        this.name = _name;
        this.age = _age;
        this.weight = _weight;
        this.height = _height;
        document.writeln("this.name=" + this.name + ",this.age=" + this.age + ",this.weight=" + this.weight + ",this.height=" + this.height);
    },
    /*public方法*/
    show : function ()
    {
        document.writeln("show method");
    }
};

/*定义一个Person类*/
function Person(_name, _age, _price)
{
    this.name = _name;
    var age = _age;
    //私有属性，只能在类内部使用
    var price = _price;
    //私有属性，只能在类内部使用
    function privateFn()
    {
        console.log("我是Pet类的私有属性age，只能在Pet类内部使用，初始化后age=" + age);
        console.log("我是Pet类的私有函数privateFn，只能在Pet类内部使用");
    }
    var privateFn2 = function ()
    {
        console.log("我是Pet类的私有属性price，只能在Pet类内部使用，初始化后price=" + price);
        console.log("我是Pet类的私有函数privateFn2，只能在Pet类内部使用");
    }
    privateFn();
    //在Pet类内部调用私有方法
    privateFn2();
    //在Pet类内部调用私有方法
}
Pet.prototype = 
{
    setName : function (_name)
    {
        this.name = _name;
    },
    getName : function ()
    {
        return this.name;
    },
    show : function ()
    {
        console.log("公开方法show");
    }
};