js代码
// 点击按钮，返回顶部
function topFunction() {
document.getElementsByClassName('layui-body')[0].scrollTop = 0;
}
function scrollFun() {
var layuiBodyScrollTop = document.getElementsByClassName('layui-body')[0].scrollTop
console.log(layuiBodyScrollTop)
if (layuiBodyScrollTop > 1000) {
document.getElementById("back-to-top").style.display = "block";
} else {
document.getElementById("back-to-top").style.display = "none";
}
}
/*注册事件*/
if (document.addEventListener) {
document.addEventListener('DOMMouseScroll', scrollFun, false);
}//W3C
window.onmousewheel = document.onmousewheel = scrollFun;//IE/Opera/Chrome
需要注意的是, 你必须要确定好鼠标滚动所绑定的DOM元素到底是什么.例如, layui中的页面滚动绑定的是 document.getElementsByClassName('layui-body')
css代码
#back-to-top {
display: none;
position: fixed;
bottom: 10px;
right: 20px;
z-index: 99999999999999;
border: none;
outline: none;
background-color: #009688;
color: white;
cursor: pointer;
padding: 5px;
border-radius: 10px;
}
#back-to-top:hover {
background-color: #23262E;
}
前端HTML部分:
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<!-- 强制让文档与设备的宽度保持1：1 -->
<meta name="viewport"
content="width=device-width, initial-scale=1, minimum-scale=1, maximum-scale=1, user-scalable=no">
<link href="/assets/logo.jpg" rel="shortcut icon" type="image/x-icon"/>
<title>MicroTek</title>
<link rel="stylesheet" href="/assets/layui/css/layui.css">
<style>
.layui-body {
left: 40px;
}
.layui-layout-admin .layui-footer {
left: 0;
}
.layui-layout-admin .layui-body {
bottom: 0;
}
.layui-card-header {
border-bottom: 0;
}
.layui-card {
box-shadow: 0 0 0 0 rgba(0, 0, 0, .05);
}
</style>
<link href="/bower_components/bootstrap/dist/css/bootstrap-theme.css" rel="stylesheet">
<link href="/bower_components/bootstrap-table/src/bootstrap-table.css" rel="stylesheet">
<link href="/bower_components/bootstrap/dist/css/bootstrap.css" rel="stylesheet">
<link href="/bower_components/pnotify/src/pnotify.css" rel="stylesheet">
<link href="/app.css" rel="stylesheet">
</head>
<body class="layui-layout-body">
<button onclick="topFunction()" id="back-to-top" title="回顶部">返回顶部</button>
<div class="layui-layout layui-layout-admin">
<div class="layui-header">
<div class="layui-logo">
<img src="/assets/logo.jpg" style="height: 2.5em ;width: 2.5em">
<a href="/" style="color: #009688;font-size: 1.2em;">微技 GD</a>
</div>
<!-- 头部区域（可配合layui已有的水平导航） -->
<ul class="layui-nav layui-layout-left">
<li class="layui-nav-item"><a href="/">GD 技术流</a></li>
<li class="layui-nav-item">
<a href="javascript:;">微图</a>
<dl class="layui-nav-child">
<dd><a href="/sotu_gank_view">干货福利</a></dd>
<dd><a href="/sotu_favorite_view">精选收藏</a></dd>
</dl>
</li>
<li class="layui-nav-item">
<a href="javascript:;">爬虫任务</a>
<dl class="layui-nav-child">
<dd><a href="/knowledge/doCrawJianShu" target="_blank">抓取简书</a></dd>
<dd><a href="/knowledge/doCrawSegmentFaultKnowledge" target="_blank">抓取SegmentFault</a></dd>
<dd><a href="/knowledge/doCrawOSChinaKnowledge" target="_blank">抓取OSChina</a></dd>
<dd><a href="/knowledge/doCrawITEyeKnowledge" target="_blank">抓取ITEye</a></dd>
<dd><a href="/knowledge/doCrawImportNewKnowledge" target="_blank">抓取ImportNew</a></dd>
<dd><a href="/knowledge/doCrawCNBlogKnowledge" target="_blank">抓取CNBlog</a></dd>
<dd><a href="/knowledge/doCrawInfoQKnowledge" target="_blank">抓取InfoQ</a></dd>
<dd><a href="/knowledge/doCrawBlockChainKnowledge" target="_blank">BlockChain</a></dd>
<dd><a href="/knowledge/KnowledgeCrawlerOfSpring4All" target="_blank">Spring4All</a></dd>
<dd><a href="/knowledge/KnowledgeCrawlerOfConcurrentProgramming" target="_blank">并发编程网</a></dd>
<dd></dd>
<dd><a href="/doGankImageCrawJob">干货福利</a></dd>
</dl>
</li>
<li class="layui-nav-item">
<a href="javascript:;">解决方案</a>
<dl class="layui-nav-child">
<dd><a href="javascript:;">列表一</a></dd>
<dd><a href="javascript:;">列表二</a></dd>
<dd><a href="">超链接</a></dd>
</dl>
</li>
<li class="layui-nav-item"><a href="">机器人管理</a></li>
<li class="layui-nav-item"><a href="">发布服务</a></li>
<li class="layui-nav-item"><a href="">用户管理</a></li>
<li class="layui-nav-item">
<a href="javascript:;">其它系统</a>
<dl class="layui-nav-child">
<dd><a href="">邮件管理</a></dd>
<dd><a href="">消息管理</a></dd>
<dd><a href="">授权管理</a></dd>
</dl>
</li>
</ul>
<ul class="layui-nav layui-layout-right">
<li class="layui-nav-item">
<a href="javascript:;">微技</a>
<dl class="layui-nav-child">
<dd><a href="">基本资料</a></dd>
<dd><a href="">安全设置</a></dd>
</dl>
</li>
<li class="layui-nav-item"><a href="">退了</a></li>
</ul>
</div>
<div class="layui-body">
....
锚点位置:
<button onclick="topFunction()" id="back-to-top" title="回顶部">返回顶部</button>
