js遍历radio代码

1. function   getRadioBoxValue(radioName)   
2.   {   
3.             var obj = document.getElementsByName(radioName);             //这个是以标签的name来取控件  
4.                  for(i=0; i<obj.length;i++)    {   
5.   
6.                   if(obj[i].checked)    {   
7.                           return   obj[i].value;   
8.                   }   
9.               }           
10.              return "undefined";         
11.   }