倒计时原生js

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>倒计时</title>
	<style type="text/css">
        body,div{margin:0;padding:0;font-family:"微软雅黑";font-size:16px;}
        #div1{letter-spacing:3px;width:300px;height:50px;position:absolute;left:50%;top:50%;margin-left:-150px;margin-top:-50px;background:#ff6000;line-height:50px;text-align:center;}
	</style>
</head>
<body>
	 <div id="div1">fr</div>
	 <script type="text/javascript">
	     function addZero(val){
	     	  return val<10?("0"+val):val
	     }

	     function getTimer(nowTime,targetTime){

	         if(targetTime>nowTime){
		          var spanTime = targetTime.getTime()-nowTime.getTime(); // 
		          // 总的毫秒差 =指定时间距离1970.1.1的毫秒差 -当前时间距离1970.1.1的毫秒差
		          var spanDay = Math.floor(spanTime/(1000*60*60*24));    // 总的毫秒数换算成天数
		          var aDay = spanDay*24*60*60*1000;   // 天数占用的毫秒数
		          var spanHours = Math.floor((spanTime-aDay)/(1000*60*60)); //总的毫秒差 换算成小时
		          var aHours =spanHours*60*60*1000; // 小时占用的毫秒
		          var spanMinute = Math.floor((spanTime-aDay-aHours)/(1000*60)); //总的毫秒差换算成分钟
		          var aMinute = spanMinute*1000*60;  // 分钟暂用的毫秒数
		          var spanSec = Math.floor((spanTime-aDay-aHours-aMinute)/1000); //总的毫秒差换算成秒
		          var str = "倒计时:"+addZero(spanDay)+"天"+addZero(spanHours)+"时"+addZero(spanMinute)+"分"+addZero(spanSec);
		          
	          }else{
	          	  var str="00:00:00"
	          }

	          return str;
        }  

     
        var nowTime = new Date();  // 获取当前时间
        var targetTime = new Date("2015/4/23 01:00:00");  // 获取指定时间
        var oDiv =document.getElementById("div1");
        oDiv.innerHTML  =getTimer(nowTime,targetTime);
        var timer = setInterval(function(){
        	var nowTime = new Date();  // 获取当前时间
	        var targetTime = new Date("2015/4/23 01:00:00");  // 获取指定时间
	        var oDiv =document.getElementById("div1");
            oDiv.innerHTML=getTimer(nowTime,targetTime);
        },1000)
	 </script>
</body>
</html>

  

posted @ 2015-04-19 18:15  jnpd  阅读(174)  评论(0编辑  收藏  举报