使用javaScript实现简单倒计时功能

效果如下：

<div class="warp">
    <p id="txt">距离”十一“国庆放假还有：</p><br>
    <p id="time"></p>
</div>

javaScript源码：

<script>
    $(document).ready(function(e) {
        
        function timer()
        {
            //获取系统当前时间
            var seconds;
            var minutes;
            var hours;
            var days;
            var year;
            var mouth;
            
            var date = new Date();
            seconds = date.getSeconds();
            minutes = date.getMinutes();
            hours = date.getHours();
            year = date.getFullYear();
            mouth = date.getMonth()+1;
            days = date.getDate();
            
            //因为Date获取的当前时间月份是0-11，少一个月，因此需先获取到各个时间后，重新定义当前时间
            var shiyi = new Date(2015,10,1,0,0,0);
            var nowDate = new Date(year,mouth,days,hours,minutes,seconds);
            
            var shiyiTime = shiyi.getTime();
            var nowTime = nowDate.getTime();
            
            var cTime = shiyiTime - nowTime;
            var cDD = checkTime(parseInt(cTime/(1000*60*60*24),10));
            var cHH = checkTime(parseInt(cTime/1000/60/60%24,10));
            var cMM = checkTime(parseInt(cTime/1000/60%60,10));
            var cSS = checkTime(parseInt(cTime/1000%60,10));
            
            function checkTime(i)
            {
                if(i < 10)
                {
                    i = "0" + i;    
                }    
                return i;
            }
            
            document.getElementById("time").innerHTML = cDD+"天"+cHH+"时"+cMM+"分"+cSS+"秒";
        }
        setInterval(timer,1000);
           
    });
</script>