一、创建对象的几种方式

       1、工厂模式：缺点是不知道对象类型

function createPerson(age) {    var o = new Object();    o.age = age    o.sayAge = function() {        alert(this.age);    }    return o;}var p1 = createPerson(11);var p1 = createPerson(12);

       2、构造函数模式:缺点就是每一次new Person的时候都是创建一个Function对象实例（sayAge）

function Person(age) {   this.age = age;   this.sayAge = function() {       alert(this.age);    }}var p1 = new Person(11);var p2 = new Person(12);

       3、原型模式:缺点数据共享的问题

           hasOwnProperty可以检测属性是实例属性还是原型中的属性;

           in:对象能够访问属性的时候返回true;

function Person() {}Person.prototype={     constructor:Person,     name:"gt",     friends:['a','b'],     sayName:functon(){         alert(this.name);     }     };var p1 = new Person();var p2 = new Person();p1.friends.push('c');这样p1和p2都有朋友c这就是他们的问题所在

       4、组合使用构造函数模式和原型模式

             目前使用的最为广泛的一种模式

function Person(age) {    this.age=age;}Person.prototype = {    constructor:Person,    sayAge:function(){        alert(this.age);    }}var p1 = new Person(11);var p2 = new Person(12);

       5、动态原型模式

function Person(age) {    this.age=age;    if(typeof this.sayName != "function") {        Person.portotype.sayName = function() {            alert(this.name)        }    }}var p1 = new Person(11);

       6、寄生构造函数模式

function SpecialArray() {    var values = new Array();    values.push.apply(values,arguments);    values.toPipedString  = function() {        return this.join('|');    }    return values;}var colors = new SpecialArray('a','b');

       7、稳妥构造函数模式:没有公共属性，而且其方法也没引用this的对象

function Person(age){    var o = new Object();    o.sayAge = function() {        alert(name);    }    return o;}var p1 = new Person(11);]p1.sayAge();只能通过sayAge方式来访问name,多用于比较安全的环境中

二、继承（主要通过原型链来实现）

    1、原型链

function SuperType(){    this.property = true;}SuperType.propotype.getSuperValue = function(){    return this.property;};function SubType(){    this.subProperty=false;}SubType.prototype = new SuperType();SubType.propotype.getSubTypeValue = function(){    return this.subProperty;}var instance = new SubType();alert(instance.getSuperType());

    2、借用构造函数

function SuperType(name){    this.name = name;}function SubType(){   SuperType.call(this,"nnnn");   this.age=20;}var instance = new SubType();

    3、组合继承

function SuperType(name){    this.name= name;    this.colors = [1,2,3]}SuperType.propotype.sayName= function(){    alert(this.name);};function SubType(name,age){    SuperType.call(this,name);    this.age=age;}SubType.prototype = new SuperType();SubType.prototype.constructor = SubType;SubType.propotype.sayAge= function(){    alert(this.age);}var instance = new SubType('aaaa',20);instance.colors.push(4);

    4、原型式继承

function object(0) {    function F(){}    F.prototype=o;    return new F();}var person = {    name='1111';    friends=[1,3];}var p1 = object(person);var p2 = object(person);friends会被共享//用Object.create方法实现 var p1 = Object.create(person);var p2 = Object.create(person);

    5、寄生式继承

function object(0) {    function F(){}    F.prototype=o;    return new F();}function createAnother(original) {    var clone = object(original);    clone.sayHi = function() {       alert('hi');    }}var person = {    name='1111';    friends=[1,3];}var p1 = createAnother(person);p1.sayHi();

    6、寄生组合式继承

function object(0) {    function F(){}    F.prototype=o;    return new F();}function inheritPrototype(subType,SuperType) {    var prototype=object(super.prototype);    prototype.constructor = subType;    subType.prototype=prototype;}function SuperType(name){     this.name = name;     this.colors = [1,2,3,4];}SuperType.prototype.sayName = function(){    alert(this.name);}function SubType(name,age) {    SuperType.call(this,name);    this.age = age}inheritPrototype(SubType,SuperType);SubType.prototype.sayAge = function(){     alert(this.age);}