javascript 活动倒计时

var nowtime = new Date(<?php echo time();?>*1000).getTime();
function liftTime(end, txt){
if(end > 0) {

var endtime = new Date(end).getTime();

var youtime = endtime-nowtime;

var seconds = youtime/1000;
var minutes = Math.floor(seconds/60);
var hours = Math.floor(minutes/60);
var days = Math.floor(hours/24);
var CHour= hours % 24;
var CMinute= minutes % 60;
var CSecond= Math.floor(seconds%60);

if(endtime <= nowtime){
window.location.reload();
}
else {
$('#tstr').html("<em>"+txt+"</em><span>"+formetNum(days)+"</span><em>天</em><span>"+formetNum(CHour)+"</span><em>时</em><span>"+formetNum(CMinute)+"</span><em>分</em><span>"+formetNum(CSecond)+"</span><em>秒</em>");

nowtime += 1000;
setTimeout("liftTime("+end+", '"+txt+"')",1000);
}

}
else {
$('#tstr').html("<em>"+txt+"</em><span>00</span><em>天</em><span>00</span><em>时</em><span>00</span><em>分</em><span>00</span><em>秒</em>");
}

}

function formetNum(num) {
if(num < 10) {
return "0"+num;
}
else {
return num;
}
}

/**
* 页面初始化
*/
$(document).ready(function(){
<?php
$time = time();
if($time < $row['star_date']) {
?>liftTime(<?php echo $row['star_date']?>*1000,"距开始还剩");<?php
}
else if($time < $row['end_date']) {
?>liftTime(<?php echo $row['end_date']?>*1000,"距结束还剩");<?php
}
else {
?>liftTime(0,"活动已结束");<?php
}
?>
});