Confirm有返回值使用

    <SCRIPT language=javascript>
       function getMessage()
       {
         var ans;
         ans=window.confirm('Is it your confirmation.....?'); //返回值True或者False         
         if (ans==true)
         {    
             document.Form1.hdnbox.value='Yes';  
         }
         else
          {   
            document.Form1.hdnbox.value='No';
          }
       }
     </SCRIPT>