JS时间动态显示

<script language='javascript'>  
function su() 
{  
      var tody=new Date();  
      var nian=tody.getFullYear();  
      var youe=tody.getMonth()+1;  
      var day=tody.getDate();  
      var hour=tody.getHours();  
      var min=tody.getMinutes();  
      var miao=tody.getSeconds();   
      document.body.innerHTML="今天是"+nian+"年"+youe+"月"+day+"日"+hour+"时"+min+"分"+miao; 
} 
setInterval("su();",1000); 
</script>