<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
</head>
<body>
<h1 id ="date_time"></h1>
<script type="text/javascript">
function getWeek(){
// case 0:
// return "星期日";
// case 1:
// return "星期一;
// case 2:
// return "星期二";
// case 3:
// return "星期三";
// case 4:
// return "星期四";
// case 5:
// return "星期五";
// case 6:
// return "星期六";
var week ="日一二三四五六".charAt(Option);
return"星期"+week;
}
function showTime(){
var dateTime = new Date();
var year = dateTime.getFullYear();
var month = dateTime.getMonth()+1;
month=month<10?"0"+month:month;
var date = dateTime.getDate();
date = date<10?"0"+date:date;
var hour = dateTime.getHours();
hour = dateTime.getHours();
hour =hour<10?"0"+hour:hour;
var minute = dateTime.getMinutes();
minute = minute<10?"0"+minute:minute;
var second = dateTime.getSeconds();
second =second<10?"0"+second:second;
var day=dateTime.getDay();
var week =getWeek(day);
dateTime = year+"年"+month+"月"+date+"日"+" "+week+" "+hour+":"+minute+":"+second;
document.getElementById("date_time").innerHTML=dateTime;
}
showTime();
setInterval("showTime()",1000)
</script>
</body>
</html>
原文：https://www.cnblogs.com/imetal/p/14849372.html