<!DOCTYPE html>
<html>

	<head>
		<meta charset="UTF-8">
		<title>定时器</title>
	</head>

	<body>
		<a href="demo05history.html">打开第五个页面</a>
		<br />
		<input type="button" value="五秒钟时候显示当前时间" onclick="showTime5()" />
		<input type="button" value="关闭五秒钟的闹钟" onclick="closeTime5()" />
		<br /> <input type="button" value="打开时钟" onclick="openClock()" />
		<input type="button" value="关闭时钟" onclick="closeClock()" />
		<br />
		<script type="t