<script type="text/javascript">
var sec =60,min=59,hour = 1
var idt = window.setInterval("ls()", 1000)
var format = function(str){
if(parseInt(str) <10){
return "0" + str
}
return str
}
function ls() {
sec--
if(sec == 0){
min--
sec = 59
}
if(min <0 &&hour >0){
hour--
min = 59
}
document.getElementById("rest_time").innerText = format(hour) + ":" + format(min) + ":" + format(sec)
if (parseInt(hour)==0&&parseInt(min)==0&&parseInt(sec)==0) {
window.clearInterval(idt)
//document.getElementById("btn_ok").click()
alert('考试时间已到，试卷已提交，感谢使用本系统！')
}
}
</script>
JS实现倒计时(时、分，秒)var
interval
=
1000
function
ShowCountDown(year,month,day,divname)
{
var
now
=
new
Date()
var
endDate
=
new
Date(year,
month-1,
day)
var
leftTime=endDate.getTime()-now.getTime()
var
leftsecond
=
parseInt(leftTime/1000)
//var
day1=parseInt(leftsecond/(24*60*60*6))
var
day1=Math.floor(leftsecond/(60*60*24))
var
hour=Math.floor((leftsecond-day1*24*60*60)/3600)
var
minute=Math.floor((leftsecond-day1*24*60*60-hour*3600)/60)
var
second=Math.floor(leftsecond-day1*24*60*60-hour*3600-minute*60)
var
cc
=
document.getElementById(divname)
cc.innerHTML
=
"脚本之家提示距离"+year+"年"+month+"月"+day+"日还有："+day1+"天"+hour+"小时"+minute+"分"+second+"秒"
}
window.setInterval(function(){ShowCountDown(2010,4,20,'divdown1')},
interval)
[Ctrl+A
全选
注:如需引入外部Js需刷新才能执行]
首先，获取当前时间 var a = new Date()然后拿你要比较的时间var b = new Date('2015-08-29')
与当前时间比较，var c = b-a
c就是得到的时间差,意义是两个时间相差的毫秒数。
最后相差的天数就是 var d=c/1000/3600/24
你最后对d向上取整，就是相差的天数了
