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>