javascript -- 原型对象

 1 function computer(){
 2 
 3      this.name="thinkPad 500";
 4      this.factory="联想";
 5      this.price=5000;
 6      this.size=17;
 7  }
 8  /*
 9   *读取函数中的prototype,默认情况下为空
10   */
11  for( pro in computer.prototype){
12      document.write(computer.prototype,"<br>");
13  } 
14  //没有继承原型对象中属性
15  var mycomputer=new computer();
16   for( pro in mycomputer){
17      document.write(pro,":",mycomputer[pro],"<br>");
18  } 
19  computer.prototype.interface="VAG";
20  //添加原型对象的属性
21   for( pro in computer.prototype){
22      document.write(pro,":",computer.prototype[pro],"<br>");
23  } 
24  //继承原型对象中属性
25  var mycomputer=new computer();
26   for( pro in mycomputer){
27      document.write(pro,":",mycomputer[pro],"<br>");
28  } 

 1 <script type="text/javascript">
 2 //定义一个工人
 3     function worker(){
 4         this.name="";
 5         this.address="";
 6     }
 7 //定义一个部门经理
 8     function manager(_dept){
 9         this.dept=_dept;
10     }
11 //定义继承关系
12     manager.prototype=new worker();
13 //创建计划部门经理
14     var jh=new manager("计划");
15     for(pro in jh){
16         document.write(pro,":",jh[pro],"<br>");
17     }
18 //当前jh有效没有改变原型对象中的值
19     jh.name="计划部门经理";
20     jh.address="计划部";
21     for(pro in jh){
22         document.write(pro,":",jh[pro],"<br>");
23     }
24 //原型对象中的值没有被修改
25     var rs=new manager(‘人事‘);
26     for(pro in rs){
27         document.write(pro,":",rs[pro],"<br>");
28     }
29 //修改原型对象中的值，将会在继承的对象中体现,如果继承类中没有覆盖
30 
31 manager.prototype.address="成都市";
32 //覆盖后address的值还是原来的计划
33 for(pro in jh){
34         document.write(pro,":",jh[pro],"<br>");
35     }
36 //没有覆盖address的值是成都市
37 for(pro in rs){
38         document.write(pro,":",rs[pro],"<br>");
39 }
40     
41 </script>