js倒计时如火车站买火车票后15分钟必须付款否则取消火车票

js倒计时如火车站买火车票后15分钟必须付款否则取消火车票

假设购买火车票下单的时间是dateTime(date 类型),然后倒计时15分钟

$(function(){     timer();});function timer(){   interval = setInterval("timer1()",1000);}function timer1(){var leftTime =  new Date().getTime() -  dateTime.getTime();leftTime = 15*60*1000  - leftTime;    var minute =parseInt(leftTime/1000/60%60,10); var second = parseInt(leftTime/1000%60,10);var min = checkTime(minute);var sec = checkTime(second);$("#leftTimeTag").html(min + ":" + sec);        if(leftTime < 1000){alert("hello 倒计时结束");clearInterval(interval);      }}function checkTime(i){if(i < 10 ){i = "0" + i;}return i;}