修改为外部引用js1文件后就出问题了
老师提供的源文件修改为外部引用后，调试工具一直提示
ReferenceError: area is not defined
修改后的代码如下（css部分略去），大家帮忙分析一下
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html部分
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title></title>
<link rel="stylesheet" href="css/style.css" />
</head>
<body>
<!-- 慕课网课程公告开始 -->
<div id="mooc">
<!-- 头部 -->
<h3 id="moocTitle">最新课程<a href="#" target="_self">更多>></a> </h3>
<!-- 头部结束 -->
<!-- 中间 -->
<div id="moocBox">
<ul id="con1">
<li><a href="#">1.学会html5 绝对的屌丝逆袭（案例）</a><span>2013-09-18</span></li>
<li><a href="#">2.tab页面切换效果（案例）</a><span>2013-10-09</span></li>
<li><a href="#">3.圆角水晶按钮制作（案例）</a><span>2013-10-21</span></li>
<li><a href="#">4.HTML+CSS基础课程(系列)</a><span>2013-11-01</span></li>
<li><a href="#">5.分页页码制作（案例）</a><span>2013-11-06</span></li>
<li><a href="#">6.导航条菜单的制作（案例）</a><span>2013-11-08</span></li>
<li><a href="#">7.信息列表制作(案例)</a><span>2013-11-15</span></li>
<li><a href="#">8.下拉菜单制作(案例)</a><span>2013-11-22</span></li>
<li><a href="#">9.如何实现“新手引导”效果</a><span>2013-12-06</span></li>
</ul>
<ul id="con2">
</ul>
</div>
<!-- 中间结束 -->
</div>
<!-- 慕课网课程公告结束 -->
<script type="text/javascript" src="js/script.js" ></script>
</body>
</html>
---------------------------------
js部分
window.onload=function(){
var area = document.getElementById('moocBox');
var con1 = document.getElementById('con1');
var con2 = document.getElementById('con2');
var speed = 50;
area.scrollTop = 0;
con2.innerHTML = con1.innerHTML;
var myScroll = setInterval("scrollUp()",speed);
area.onmouseover = function(){
clearInterval(myScroll);
}
area.onmouseout = function(){
myScroll = setInterval("scrollUp()",speed);
}
}
function scrollUp(){
if(area.scrollTop >= con1.scrollHeight) {
area.scrollTop = 0;
}else{
area.scrollTop ++;
}
}
