封装的倒计时方法

function downTime (time) {//time是结束时间

var timesNow = Date. parse ( new Date()); //当前时间

var leftTime = time - timesNow ; //剩余时间

var leftsecond = parseInt ( leftTime / 1000 ); //剩余秒数

var day_1 = Math . floor ( leftsecond / ( 60 * 60 * 24 )); //剩余天数

var hour = Math . floor (( leftsecond - day_1 * 24 * 60 * 60 ) / 3600 ); //剩余小时

var minute = Math . floor (( leftsecond - day_1 * 24 * 60 * 60 - hour * 60 * 60 ) / 60 ); //剩余分钟

var second = Math . floor ( leftsecond - day_1 * 24 * 3600 - hour * 3600 - minute * 60 ); //剩余秒数

hour = checkTime ( hour );

minute = checkTime ( minute );

second = checkTime ( second );

str = "" + day_1 + "天" + hour + "时" + minute + "分 " + second + "秒" ;

return str ;

function checkTime (i) { //将0-9的数字前面加上0，例1变为01

if (i < 10 ) {

i = "0" + i;

}

return i;

}

}

最后定时器执行函数：

setInterval(downTime(time),1000);