javascript变化的时钟

<script language="JavaScript">
<!--
function check(val){
 if (val<10){
  return("0"+val);
 }else{
  return(val);
 }
}
function ShowTime()
{
 var date=new Date();
 var year=date.getFullYear();
 var month=date.getMonth()+1;
 var day=date.getDate();
 var hour=date.getHours();
 var minutes=date.getMinutes();
 var second=date.getSeconds();
 var timestr=year+"-"+ month+"-"+ day+ " " + +check(hour)+":"+check(minutes)+":"+check(second);
 document.getElementById("stime").innerText=timestr;
 var timerID=setTimeout('ShowTime();',1000);
}
//-->
</script>