javascript面向对象实例属性和实例方法

<script language="javascript" type ="text/javascript">
function Person(){
this.name = "小白";
this.age = "20";
this.say = function(){
document.write("我的姓名是："+this.name+"，我的年龄是："+this.age);
}
}
var person1 = new Person();
var person2 = new Person();
person2.name = "php点点通";
person2.age = "22";
document.write("我的姓名是："+person1.name+"，我的年龄是："+person1.age);
document.write("<hr />我的姓名是："+person2.name+"，我的年龄是："+person2.age);
</script>