一、基础知识

获取时间对象  var date=new Date();
date.getFullYear()	   	 获取年
date.getMonth()+1     	 获取月，国外0-11
date.getDate()		  	 获取哪一天
date.getDay()		 	 获取星期几
date.getHours()	     	 获取小时
date.getMinutes()	  	 获取分钟
date.getSeconds()	  	 获取秒
date.getMilliseconds()   获取毫秒 ，1秒=1000毫秒
date.getTime()		     获取的是1970-1-1到现在的毫秒数

二、动态显示系统当前时间

1.代码

代码如下（示例）：

<!DOCTYPE html>
<html><head><meta charset="utf-8"><title></title><style>#wrapper {width: 400px;height: 80px;border: 2px solid red;margin: 0 auto;line-height: 80px;text-align: center;}</style></head><body><div id="wrapper"></div><script>var _wrapper = document.querySelector("#wrapper");function test() {var date = new Date();var year = date.getFullYear(); //2022年var month = date.getMonth() + 1; //8月,国外0-11var day = date.getDate(); //1号var week = date.getDay(); //1，星期一//调用转换星期的函数week = switchWeek(week);var hours = date.getHours();hours = switchZero(hours);var minutes = date.getMinutes();minutes = switchZero(minutes);var seconds = date.getSeconds();seconds = switchZero(seconds);_wrapper.innerHTML = `${year}年${month}月${day}日&emsp;${week}&emsp;${hours}:${minutes}:${seconds}`}setInterval("test()", 1000);//星期转换function switchWeek(days) {var res;if (days == 0) {res = "星期日"}if (days == 1) {res = "星期一"}if (days == 2) {res = "星期二"}if (days == 3) {weeks = "星期三"}if (days == 4) {res = "星期四"}if (days == 5) {res = "星期五"}if (days == 6) {res = "星期六"};return res;}//拼0转换function switchZero(time) {if (time < 10) {time = "0" + time;}return time;}</script></body>
</html>