<script>var $ = document.getElementById("subnav");
var items = $.getElementsByTagName("li");for(i=0;i<items.length;i++){
if(items[i].onmouseover) {
items[i].getElementsByTagName("span").style.display = 'block';
}
}</script>运行的时候不提示错误 但是不显示效果 谢谢
var items = $.getElementsByTagName("li");for(i=0;i<items.length;i++){
if(items[i].onmouseover) {
items[i].getElementsByTagName("span").style.display = 'block';
}
}</script>运行的时候不提示错误 但是不显示效果 谢谢
<!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>万恶的弹出菜单</title>
<style>
body,ul,li{margin:0;padding:0; font-size:14px;}
ul{list-style:none; position:relative;}
.nav{margin:0 auto; background:url(topnav_stretch.gif) repeat-x; width:500px;height:35px;}
#subnav li{ float:left;}
#subnav li span{background: #1376c9; width:500px;height:35px; position:absolute; display:none;}
a{ color:#FFF; text-decoration:none; display:block; padding:10px 15px;}
a:visited{color:#FFF;}
a:hover{ background:url(topnav_active.gif) repeat-x;}</style>
</head><body>
<div class="nav">
<ul id="subnav">
<li><a href="#">首页</a></li>
<li>
<a href="#">博客</a>
<span>
<a href="#">博客</a>
<a href="#">博客</a>
<a href="#">博客</a>
</span>
</li>
<li>
<a href="#">作品</a>
<span>
<a href="#">博客</a>
<a href="#">博客</a>
<a href="#">博客</a>
</span>
</li>
<li><a href="#">图片</a></li>
<li><a href="#">关于我</a></li>
</ul><script>var $ = document.getElementById("subnav");
var items = $.getElementsByTagName("li");for(i=0;i<items.length;i++){
if(items[i].onmouseover) {
items[i].getElementsByTagName("span")[0].style.display = 'block';
}
}</script>
</div>
</body>
</html>好了.本来是想多锻炼下自己的,所以只贴了JS部分
再者需要判断一下items[i].getElementsByTagName("span")的长度
if(items[i].getElementsByTagName("span").length!=0)
items[i].getElementsByTagName("span")[0].style.display = 'block';