<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>自动展开</title>
<style type="text/css">
body
{
margin: 0 auto;
padding: 0;
}
a:focus
{
outline: none;
}
#pn
{
background: #e8e8e8;
height: auto;
width: 960px;
display:block;
margin: 0 auto;
padding: 5px;
text-align: center;
}
.slide
{
padding: 10px;
width: 950px;
margin: 0 auto;
background: gray;
text-align: center;
height: 40px;
line-height: 40px;
color: #fff;
}
</style>
<script type="text/javascript">
var h=0;
//增加高度函数addH()
function addh() {
if(h<300){
h=h+5;
document.getElementById('pn').style.height=h+"px";
}else{
return;
}
setTimeout("addh()",30);
}
//网页加载完毕时，调用增加高度函数addH()，等待5秒钟后调用减少高度函数subh()。
window.onload=function(){
addh();
setTimeout("subh()",5000);
}
// 减少高度函数subH()
function subh() {
if(h>0){
h=h-5;
document.getElementById('pn').style.height=h+"px";
}else{
return;
document.getElementById('pn').style.display="none";
}
setTimeout("subh()",30);
}
</script>
</head>
<body>
<div id="pn">
<h1>
欢迎来到慕课网</h1>
<h2>
大幅广告</h2>
</div>
<p class="slide">
慕课网欢迎你</p>
</body>
</html>
艾西西