<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>无标题文档</title>
</head>
<body>
<div id="div1"></div>
</body>
</html>
<script>
window.onload = function(){
var oDiv = document.getElementById(‘div1‘); //最后获取
function timego(){
var now = new Date();
var year = now.getFullYear();
var month = now.getMonth()+1;
var date = now.getDate();
var week = now.getDay();
var hour = now.getHours();
var minute = now.getMinutes();
var second = now.getSeconds();
var str = ‘当前时间是：‘+ year + ‘年‘+month+‘月‘+date+‘日 ‘+toweek(week)+‘ ‘+todou(hour)+‘:‘+todou(minute)+‘:‘+todou(second);
oDiv.innerHTML = str ;
}
timego();
setInterval(timego,1000);
}
function toweek(n){
if(n==0)
{
return ‘星期日‘;
}
else if(n==1)
{
return ‘星期一‘;
}
else if(n==2)
{
return ‘星期二‘;
}
else if(n==3)
{
return ‘星期三‘;
}
else if(n==4)
{
return ‘星期四‘;
}
else if(n==5)
{
return ‘星期五‘;
}
else
{
return ‘星期六‘;
}
}
function todou(n){
if(n<10)
{
return ‘0‘+n;
}
else
{
return n;
}
}
</script>
原文：https://www.cnblogs.com/wjr2018/p/10260005.html