一.获取日期时间，秒数实时跳动
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>date01</title>
<style>
#date{
position: absolute;
font-size: 30px;
font-family: '微软雅黑';
top:50%;
left:50%;
-webkit-transform:translate(-50%,-50%);
}
</style>
</head>
<body>
<div id="date">2017.10.29</div>
<script>
window.onload = function(){
showTime();
}
//checkTime(i)对分钟和秒进行判断，如果小于10，在其前补0.
function checkTime(i){
return i < 10? "0"+i:i;
}
function showTime(){
var time = new Date();//日期对象
console.log("new Date :"+time);
var year_1 = time.getYear();//获得年份
console.log("getYear(): "+year_1);
var year_2 = time.getFullYear();//获得完整年份
console.log("getFullYear(): "+year_2);
var month = time.getMonth();//获得月份(0~11)
console.log("getMonth(): "+month);
var date = time.getDate();//获得日期(1~31)
console.log("getDate(): "+date);
var day = time.getDay();//星期几(0~6)
console.log("getDay(): "+day)
var hours = time.getHours();//小时(0~23)
console.log("getHours(): "+hours);
var min = time.getMinutes();//分钟(0~59)
console.log("getMinutes(): "+min);
var seconds = time.getSeconds();//秒
console.log("getSeconds(): "+seconds); min = checkTime(min);
seconds = checkTime(seconds); var weekday = new Array(7);
weekday[0] = "星期天";
weekday[1] = "星期一";
weekday[2] = "星期二";
weekday[3] = "星期三";
weekday[4] = "星期四";
weekday[5] = "星期五";
weekday[6] = "星期六"; var str_time = year_2 + "年" + (month+1) + "月" + date + "日" +" "+ weekday[day] +" "+ hours +":" + min +":" + seconds; document.getElementById('date').innerHTML = str_time;
setTimeout(showTime,500);//每500ms执行一次，实现秒数实时跳动。
} </script>
</body>
</html>
二.高考倒计时功能（天）
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>date02</title>
<style>
#date{
position: absolute;
font-size: 30px;
font-family: '微软雅黑';
top:50%;
left:50%;
-webkit-transform:translate(-50%,-50%);
}
</style>
</head>
<body>
<div id="date">2017.10.29</div>
<script>
window.onload = function(){
var now = new Date();//获取当前时间
var timedate = new Date("2018,12,23");//截止时间
//getTime() 方法可返回距 1970 年 1 月 1 日之间的毫秒数。
var date = timedate.getTime() - now.getTime();
//Math.ceil()向上取整
var time = Math.ceil(date/(24*60*60*1000));
document.getElementById('date').innerHTML = time; }
</script>
</body>
</html>
三.限时抢
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>date03</title>
<style>
#date{
position: absolute;
font-size: 30px;
font-family: '微软雅黑';
top:50%;
left:50%;
-webkit-transform:translate(-50%,-50%);
}
</style>
</head>
<body>
<div id="date">2017.10.29</div>
<script>
window.onload = function(){
showTime(); }
function checkTime(i){
return i < 10? "0"+i:i;
}
function showTime(){
var now = new Date();//获取当前时间
var timedate = new Date("2017/10/30,24:00:00");//截止时间
//getTime() 方法可返回距 1970 年 1 月 1 日之间的毫秒数。
var leftTime = (timedate.getTime() - now.getTime())/1000;
var d = checkTime(parseInt(leftTime/(24*60*60)));
var h = checkTime(parseInt(leftTime/(60*60)%24));
var m = checkTime(parseInt(leftTime/60%60));
var s = checkTime(parseInt(leftTime%60));
var time = d + "天" + h + "小时" + m + "分钟" + s + "秒";
document.getElementById('date').innerHTML = time;
setTimeout(showTime,500);
}
</script>
</body>
</html>