<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title><script>// 格式化日期 年月日var date =newDate();
console.log(date.getFullYear());//返回当前日期的年
console.log(date.getMonth()+1);
console.log(date.getDate());//返回的是 几号
console.log(date.getDay());// 周一返回的是1 周六返回的是6 但是周日返回的是0// 案例:获取当前系统时间 2021年11月24日 星期三var date =newDate();var year = date.getFullYear();var month = date.getMonth()+1;var dates = date.getDate();var arr =['星期日','星期一','星期二','星期三','星期四','星期五','星期六'];var day = date.getDay();
console.log('今天是:'+ year +'年'+ month +'月'+ dates +'日 '+ arr[day]);</script></head><body></body></html>
3.2、获取特定格式的系统当前日期的时分秒
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title><script>// 格式化日期时分秒var date =newDate();
console.log(date.getHours());//时
console.log(date.getMinutes());//分
console.log(date.getSeconds());//秒// 要求封装一个函数返回当前的时分秒 格式 08:08:08functiongetTimer(){
var time =newDate();var h = time.getHours();
h = h <10?+'0': h;var m = time.getMinutes();
m = m <10?+'0': m;var s = time.getSeconds();
s = s <10?+'0': s;return h +':'+ m +':'+ s;}
console.log(getTimer());</script></head><body></body></html>
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>Document</title><script>functioncountDown(time){
var nowTime =+newDate();//返回的是当前时间的总毫秒数var inputTime =+newDate(time);//返回的是用户输入时间的总毫秒数var times =(inputTime - nowTime)/1000;//times是剩余时间总的秒数var d =parseInt(times /60/60/24);//天
d = d <10?'0'+ d : d;var h =parseInt(times /60/60%24);//时
h = h <10?'0'+ h : h;var m =parseInt(times /60%60);//分
m = m <10?'0'+ m : m;var s =parseInt(times %60);//当前的秒
s = s <10?'0'+ s : s;return d +'天'+ h +'时'+ m +'分'+ s +'秒';}
console.log(countDown('2021-11-24 18:00:00'));var date =newDate();
console.log(date);</script></head><body></body></html>