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<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>倒计时</title>
	<style>
		div{border:4px solid #424242;font:700 24px/36px '';width:600px; margin:0 auto;text-align: center;margin-top:50px;}
	</style>
</head>
<body>
	<div id="div1">
		
	</div>	
	<script>
		setInterval(showTime,1000);
		showTime();
		function showTime(){
			var later  = new Date(2019,6,1);
			var now = new Date();
			var delta = later.getTime() - now.getTime();//计算差值

			//变量存放天 小时 分钟 秒 的毫秒数
			var dMs = 24*60*60*1000;
			var hMs = 60*60*1000;
			var mMs = 60*1000;
			var sMs = 1000;
			//计算倒计时的值
			var d = Math.floor(delta/dMs);
			var h = Math.floor((delta-dMs*d)/hMs);
			var m = Math.floor((delta-dMs*d-hMs*h)/mMs);
			var s = Math.floor((delta-dMs*d-hMs*h-mMs*m)/sMs);

			var div1 = document.getElementById('div1');
			div1.innerHTML = '还剩:' + adjust(d) + '天' + adjust(h) + '小时' + adjust(m) +'分钟' + adjust(s) + '秒';

			function adjust(num){
				if(num < 10){
					return "0" + num;
				}
				return '' + num;
			}


		}
	</script>
</body>
</html>