JavaScript学习----Prototype 

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    <title>JavaScript Study 2015.11.9--</title>
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    <script type="text/javascript">
    //prototype的内存分析
    
    /*
    //第1种状态
    function Person(name,age){
        this.name = name;
        this.age = age;
        this.say = function(){
            alert(this.name+","+this.age);
        }
    }
    
    //第2种状态
    Person.prototype.sayHi = function(){
       alert(this.name+":sayHi");
    }
    //第3种状态
    var p1 = new Person("lili",20);
    
    //第4种状态
    p1.say();
    */
    
    
    //prototype重写的内存分析
    
    //第1种状态
    function Person(name,age){
        this.name = name;
        this.age = age;
        this.say = function(){
            alert(this.name+","+this.age);
        }
    }
    //第2种状态
    var p1 = new Person("lili",20);
    
    //第3种状态
    Person.prototype = {
         sayHi:function(){
           alert("sayHi");
         }
    }
    //第4种状态
    var p2 = new Person("disk",30);
    
    p1.say();//no error
    p2.say();//no error
    
    //p1.sayHi();//error
    p2.sayHi();//no error
    


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posted @ 2015-11-20 16:49  heavyblog  阅读(178)  评论(0)    收藏  举报