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<title>地狗购物网-网页定位导航效果</title>
<style>
*{
margin:0;
padding:0;
}
body{
font-size:12px;
line-height:1.7;
}
li{
list-style:none;
}
#content{
width:800px;
margin:0 auto;
padding:20px;
}
#content h1{
color:#08b;
}
#content .item{
padding:20px;
margin-bottom:20px;
border:1px dotted #08b;
}
#content .item h2{
font-size:16px;
font-weight:bold;
border:2px solid #08b;
margin-bottom:10px;
}
#content .item li{
display:inline;
margin-right:10px;
}
#content .item li a img{
width:230px;
height:230px;
border:none;
}
#menu{
position:fixed;
top:100px;
left:50%;
margin-left:400px;
width:80px;
}
#menu ul li a{
display:block;
margin:5px 0;
font-size:14px;
font-weight:bold;
color:#333;
width:80px;
height:50px;
line-height:50px;
text-decoration:none;
text-align:center;
}
#menu ul li a:hover,#menu ul li a.current{
color:#fff;
background:#08b;
}
</style>
<script>
function getByClassName(obj,cls){
var elements=obj.getElementsByTagName("*");
var result=[];
for(var i=0;i<elements.length;i++){
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function hasClass(obj,cls){
return obj.className.match(new RegExp("(\\s|^)"+cls+"(\\s|$)"));
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function removeClass(obj,cls){
if(hasClass(obj,cls)){
var reg=new RegExp("(\\s|^)"+cls+"(\\s|$)");
obj.className=obj.className.replace(req,"");
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}
function addClass(obj,cls){
if(!hasClass(obj,cls)){
obj.className+=" "+cls;
}
}
window.onload=function(){
window.onscroll=function(){
var top=document.documentElement?document.documentElement.scrollTop:document.body.scrollTop;
var menus=document.getElementById("menu").getElementsByTagName("a");
var items=getByClassName(document.getElementById("content"),"item");
var currentId="";
for(var i=0;i<items.length;i++){
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<body>
<div id="menu">
<ul>
<li><a href="#item1" class="current">1F 男装</a></li>
<li><a href="#item2">2F 女装</a></li>
<li><a href="#item3">3F 美妆</a></li>
<li><a href="#item4">4F 数码</a></li>
<li><a href="#item5">5F 母婴</a></li>
</ul>
</div>
<div id="content">
<h1>地狗购物网</h1>
<div id="item1" class="item">
<h2>1F 男装</h2>
<ul>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/1F.jpg" alt=""></a></li>
</ul>
</div>
<div id="item2" class="item">
<h2>2F 女装</h2>
<ul>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/2F.jpg" alt=""></a></li>
</ul>
</div>
<div id="item3" class="item">
<h2>3F 美装</h2>
<ul>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/3F.jpg" alt=""></a></li>
</ul>
</div>
<div id="item4" class="item">
<h2>4F 数码</h2>
<ul>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
<li><a href="#"><img src="image/导航/4F.png" alt=""></a></li>
</ul>
</div>
<div id="item5" class="item">
<h2>5F 母婴</h2>
<ul>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
<li><a href="#"><img src="image/导航/5F.jpg" alt=""></a></li>
</ul>
</div>
</div>
</body>
</html>
removeClass函数里的obj.className=obj.className.replace(req,"");
改成obj.className=obj.className.replace(reg,"");
if(currentId){
for(var j=0;j<menus.length;j++){
var _menu=menus[i];
中的var _menu=menus[i];
改成
var _menu=menus[j];
虽然晚了几年
把你的代码替换上去,才会显示报错
这个var top=document.documentElement?document.documentElement.scrollTop:document.body.scrollTop;;无论你怎么滚动它都等于undefined;把他改为var top=document.documentElement.scrollTop||document.body.scrollTop;
var items=getByClassName(document.getElementById("content"),"item");错误,多了一个)