為啥我的不行
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> ? ?
<title>頂部廣告展開收起</title>
<style>
body, div, img, span { margin:0; padding:0; }
#content{ width:960px; height:1000px; background:#ccc; margin:0 auto; }
#ad{ width:960px; margin:0 auto; position: relative; overflow: hidden; display:none; }
#close{
? ? position:absolute;
? ? width:20px;
height:20px;
text-align:center;
line-height:20px;
background:#CF3;
top:0;
right:0;
display: none;
cursor: pointer;
}
</style>
</head>
<body>
<div id="ad">
<img id="adcon" src="http://img1.sycdn.imooc.com//52fdb1ce0001e92d09620386.jpg" width="960" height="385"/>
<img id="adcur" src="http://img1.sycdn.imooc.com//52fdb21a0001a0eb11990068.jpg" width="960" height="80"/>
<span id="close">X</span>
</div>
<div id="content"><img src="http://img1.sycdn.imooc.com//52fdb1930001795a09601700.jpg" /></div>
<script>
//全局變量
var oAd ? ? = document.getElementById('ad');
var oAdcon ?= document.getElementById('adcon');
var oAdcur ?= document.getElementById('adcur');
var oClose ?= document.getElementById('close');
var maxH = OAdcon.height ;//最大高度
var minH = OAdcur.height ;//最小高度
var step = 5;//移動(dòng)的距離
var h ? ?= 0;
/*廣告向下展開*/
function adDown(){
oAd.style.display = "block";
oAd.style.height ?= h+"px";
if( h<maxH){
? ?h+=step; //向下移動(dòng)
setTimeout(adDown,1);
}else{
setTimeout(adUp,3000); //停留時(shí)間自己適當(dāng)調(diào)整 1000 = 1秒
}
}
/*廣告向上收起*/
function adUp(){
oAd.style.height =h+"px";
? ? ??
if( h>minH ) {
h-=step; //向上移動(dòng)
setTimeout(adUp,1);
}else {
oAdcon.style.display = "none";
oClose.style.display = "block";
}
}
oClose.onclick = function(){
oAd.style.display = "none";
}
setTimeout(adDown, 3000);
</script>
</body>
</html>
2017-04-17
var oAdcon ?= document.getElementById('adcon');
var oAdcur ?= document.getElementById('adcur');
var oClose ?= document.getElementById('close');
var maxH = OAdcon.height ;//最大高度
var minH = OAdcur.height ;//最小高度
這是你的獲取全局變量部分的代碼。你可以看看，因?yàn)槟銓戝e(cuò)了，前面是小寫o開頭，接下來就用了大寫O。就是那個(gè)oAdcon和oAdcur。然后就可以正常運(yùn)行啦