<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>tab栏的套路就是先全部隐藏，再展示这个</title>
<style>
*{margin: 0;padding: 0;}
ul{list-style: none;}
.box {
250px;
height: 300px;
margin:100px auto;
border:1px solid #ccc;
overflow: hidden;
}
.mt span {
display: inline-block;
50px;
height: 30px;
background-color: pink;
text-align: center;
line-height: 30px;
cursor: pointer;
}
.mt span.current {
background-color: purple;
}
.mb li {
100%;
height: 270px;
background-color: purple;
display: none;
}
.mb li.show {
display: block;
}
</style>
<script>
window.onload = function(){
function table(obj){
var target = document.getElementById(obj);
var spans = target.getElementsByTagName("span");
var lis = target.getElementsByTagName("li");
for(var i= 0;i<spans.length;i++)
{
spans[i].index = i; // 难点tns[i].index = i; // 难点
var sp = spans[i];
spans[i].onmouseover = function(){
for(var j=0;j<spans.length;j++)
{
spans[j].className = "";
lis[j].className = "";
}
this.className = "current";
lis[this.index].className = "show";
}
}
}
table("one");
table("two");
table("three");
}
</script>
</head>
<body>
<div class="box" id="one">
<div class="mt">
<span class="current">新闻</span>
<span>娱乐</span>
<span>体育</span>
<span>小说</span>
</div>
<div class="mb" >
<ul>
<li class="show">新闻知识</li>
<li>娱乐知识</li>
<li>体育知识</li>
<li>小说知识</li>
</ul>
</div>
</div>
<div class="box" id="two">
<div class="mt">
<span class="current">新闻2</span>
<span>娱乐</span>
<span>体育</span>
<span>小说</span>
</div>
<div class="mb" >
<ul>
<li class="show">新闻知识2</li>
<li>娱乐知识</li>
<li>体育知识</li>
<li>小说知识</li>
</ul>
</div>
</div>
<div class="box" id="three">
<div class="mt">
<span class="current">新闻3</span>
<span>娱乐</span>
<span>体育</span>
<span>小说</span>
</div>
<div class="mb" >
<ul>
<li class="show">新闻知识3</li>
<li>娱乐知识</li>
<li>体育知识</li>
<li>小说知识</li>
</ul>
</div>
</div>
</body>
</html>