Object.prototype.ext=function(parObject){//Object.prototype.ext在原型链上定义的ext所有的对象都可以访问到

     //循环遍历父类对象所有属性

     for(var i in parObject){

         //为子类对象添加这个遍历到的属性

         //它的值是父类对象这个属性的属性值

         this[i] = parObject[i];

     }

 }

 function Person(p_name,p_age){

     this.name=p_name;

     this.age=p_age;

     this.speak=function(){

         alert(this.name+this.age);

     }

 }

 function Student(p_no){

     this.no=p_no;

     this.say=function(){

         alert(this.no+this.name_this.age);

     }

 }

 var stu = new Student(101);

 stu.ext(new Person('xiaoqiang',20));

 stu.speak();

 stu.say();

 function Person(p_name,p_age){

     this.name=p_name;

     this.age=p_age;

     this.speak=function(){

         alert(this.name+this.age);

     }

 }

 function Student(p_no,p_name,p_age){

     this.no=p_no;

     this.say=function(){

         alert(this.name+this.age+this.no);

     }

     Person.call(this,p_name,p_age);//this是上下文,后面的参数是传递给person的参数,参数的先后顺序要一一对应,如果是用apply则后面的参数要用数组

 }

 var stu = new Student(8,'zhagsan',18);

 stu.speak();

 stu.say();

 function Person(p_name,p_age){

     this.name=p_name;

     this.age=p_age;

     this.speak=function(){

         alert(this.name+this.age);

     }

 }

 function Student(p_no){

     this.no=p_no;

     this.say=function(){

         alert(this.name+this.age+this.no);

     }

 }

 Student.prototype = new Person('wangwu',21);

 var stu = new Student(10);

 stu.speak();

 stu.say();