继承的话我这里主要是传统的原型继承方式。关于原型继承，这个在网上已经有现有的轮子了（参考了慕课网Bosn老师的JavaScript深入浅出一篇的原型继承的视频讲解），我就站在巨人的肩上给稍微改动了下了

Object.prototype.extends = function(SuperClass) {		if(!Object.create) {		Object.create = function(proto) {			function F() {								F.prototype = proto;				return new F;			}		}	}	var oldPrototype = this.prototype;	this.prototype = Object.create(SuperClass.prototype);	//	this.prototype.constructor = SuperClass;	for(key in oldPrototype) {		oldPrototype[key] !=undefined && (this.prototype[key]=oldPrototype[key]);	}	this.prototype.__parent__ = SuperClass;};Object.prototype.super = function() {		var param = arguments[0];	var arg = arguments;		while(param) {				if(!param.callee) {			break;		}		arg = param;		param = param[0];	}	var parent = this;		while(parent) {				for(var key in parent) {//首次子类调用该方法						if(arguments[0].callee == parent[key]) {//找到对应父类				arg.callee = arguments[0].callee;				parent.__parent__.prototype[key].apply(this, arg);				return;			}		}		for(var key in parent.prototype) {						if(arguments[0].callee == parent.prototype[key]) {//找到对应父类				arg.callee = arguments[0].callee;				parent.prototype.__parent__.prototype[key].apply(this, arg);				return;			}		}		parent = parent.__parent__;	}};Object.defineProperties(Object.prototype, {	'extends': {		enumerable: false,		writable: false	},	'super': {		enumerable: false,		writable: false	}});

使用例子：

var Person = function() {};Person.prototype = {    say: function() {        console.log("person say");    }};var Father = function() {};Father.prototype = {    say: function() {        this.super(arguments);        console.log("father say");    }}Father.extends(Person);var Son = function() {};Son.prototype = {    say: function() {        this.super(arguments);        console.log("son say");    }}Son.extends(Father);var son = new Son();son.say();var Daughter = function() {};Daughter.prototype = {    say: function() {        this.super(arguments);        console.log("daughter say");    }}Daughter.extends(Father);var daughter= new Daughter();daughter.say();

/************* 打印结果 ***************/

person sayfather sayson sayperson sayfather saydaughter say

多态主要是在方法里面通过调用this.super(arguments)就会自动向上调用父类的同名方法。以上便是本次的js代码库分享，希望大家多多指点、多多评论，也希望我以后能给大家带来更多有用的库方法或者类。欢迎转载，原文出处