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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Time</title>
<script type="text/javascript">
window.onload=function () {
  showTime();
}
  function showTime() {
   var mDate = new Date();
   var year=mDate.getFullYear();
   var month=mDate.getMonth()+1;
   var date=mDate.getDate();
   var h=mDate.getHours();
   var s=mDate.getSeconds();
   var m=mDate.getMinutes();
   var week=mDate.getDay();
   var weeks=["星期日","星期一","星期二","星期三","星期四","星期五","星期六"];
   var text=document.getElementById('timeText');
   text.innerHTML=year+"年"+month+"月"+date+"日"+weeks[week]+h+":"+m+":"+s;
   setTimeout(showTime,500);
  }

</script>
</head>
<body>
<input type="text" id="timeText" style="margin-top: 20px">
</body>
</html>