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<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>下滚固定导航条</title>
<style type="text/css">
*{margin:0;padding: 0}
.main{
height: 70px;
background: orange;
}
.box{
width:100%;
height: 60px;
background: #f7f7f7;
position: fixed;
background: red;
display: none;
}
#main{height:1500px;background: #green}
input{margin:10px auto;width:300px;height:40px;border:none;border-radius: 20px;}
</style>
<script type="text/javascript" src="static/js/jquery.js"></script>
</head>
<body>
<div class="main">
<input type="text">
</div>
<div class="box">
<input type="text">
</div>
<div id="main">
</div>
<script>
window.onload=function(){
document.onscroll=function(){
if(document.documentElement.scrollTop>100){
document.getElementsByClassName('box')[0].style.display='block';
}else{
document.getElementsByClassName('box')[0].style.display='none';
}
}
}
</script>
</body>
</html>点击 "运行实例" 按钮查看在线实例
