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<title>JavaScript Study 2015.11.9--</title>
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//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
</script>
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