JS实现继承多态

//类对象构造模版,无new访问，类似静态访问
var Class = {
    create: function () {
        return function ()
        {
            //initialize初始化
            //apply应用变更，可以反复请求
            //arguments参数
            this.initialize.apply(this, arguments)
        };
    },
    //模拟抽象方法，可以随便自己定
    Show: function () {
    }
};

//模拟继承extobj扩展对象，srcobj源对象
var Extend = function (extobj, srcobj) {
    for (var a in srcobj) {
        extobj[a] = srcobj[a];
    }
    return extobj;
};

//动态为Object添加extend方法,用来完成继承
Object.prototype.extend = function (obj) {
    return Extend.apply(this, [this, obj]);
};

//实例演示
var ClassAB = Class.create();
ClassAB.prototype = {
    //初始函数,相当于构造方法
    initialize: function (name) {
        this.name = name;
    },
    Show: function (a) {
        this.abstractShow(a); //抽象方法
    }
};

//继承
var ClassA = Class.create();
ClassA.prototype = new ClassAB(null).extend({
    Show: function (a) { //实现抽象方法
        alert(this.name + " " + typeof (this) + " " + a);
    }

});

var ClassB = Class.create();
ClassB.prototype = new ClassAB(null).extend({
    Show: function (a) { //实现抽象方法
        alert(this.toString + " " + typeof (this) + " " + a+new Date().toDateString());
    }
});

//多态
ClassAB = new ClassA("ClassA");
ClassAB.Show("hello");

ClassAB = new ClassB("ClassB");
ClassAB.Show("hello");