javascript获取<input type=radio...>的值

<script type="text/javascript">
          
    function toSubmitStatus() {
     var s_welwords_flag = document.getElementsByName("welwords_flag");
         for(var i=0; i<s_welwords_flag.length; i++) {
           if(s_welwords_flag[i].checked) {
              alert(s_welwords_flag[i].value);               break;
           }
        }   
     //alert(s_welwords_flag);
    }
   </script> 
 <table width="294" border="1">
   <tr>
    <td>欢迎词设置:
    </td>
   </tr>
    <tr>
      <td width="284"><input name="welwords_flag" type="radio" value="0" <%if(welwords_flag!=null && welwords_flag.equals("0")) {out.print("checked");} %>/>
        男 </td>
    </tr>
    <tr>
      <td><input name="welwords_flag" type="radio" value="1" <%if(welwords_flag!=null && welwords_flag.equals("1")) {out.print("checked");} %>/>
       女</td>
    </tr>
   <tr>
    <td><input type="button" name="toSubmit2" value="修改" οnclick="toSubmitStatus();"/></td>
   </tr>    
    </table>