1、新建html文档。
2、书写hmtl代码。
<body style="height:2000px;">
<div class="go-top dn" id="go-top">
<a href="#" class="uc-2vm"></a>
<div class="uc-2vm-pop dn">
<h2 class="title-2wm">用微信扫一扫</h2>
<div class="logo-2wm-box">
<img src="xin.jpg
</div>
</div>
<a href="#" target="_blank" class="feedback"></a>
<a href="#" class="go"></a>
</div>
<body>
3、书写css代码。
<style>
*{ margin:0; padding:0;}
body{background-color: #F1F1F1;color: #333}
.dn{display: none;}
.go-top{position: fixed;bottom: 40px;right: 20px;width: 46px;z-index: 999;}
.go-top a{display: block;width: 46px;height: 46px;margin-bottom: 10px;background-image: url(o-top.png?);}
.go-top a:last-child{margin-bottom: 0;}
.go-top .go{background-position: 0 -150px;}
.go-top .go:hover{background-position: 0 -250px;}
.go-top .feedback{background-position: 0 -100px;}
.go-top .feedback:hover{background-position: 0 -300px;}
.go-top .uc-2vm{background-position: 0 0;}
.go-top .uc-2vm:hover{background-position: 0 -350px;}
.go-top .uc-2vm-pop{position: absolute;right: 60px;top: -100px; width: 220px;box-shadow: 0px 1px 4px rgba(0,0,0,.1);background: #fff;}
.go-top .uc-2vm-pop .title-2wm{font-size: 14px; margin: 10px 20px;}
.go-top .uc-2vm-pop .logo-2wm-box{position: relative;}
</style>
4、书写并添加js代码。
<script src="jquery.min.js"></script>
<script>
$(function(){
$(window).on('scroll',function(){
var st = $(document).scrollTop();
if( st>0 ){
if( $('#main-container').length != 0 ){
var w = $(window).width(),mw = $('#main-container').width();
if( (w-mw)/2 > 70 )
$('#go-top').css({'left':(w-mw)/2+mw+20});
else{
$('#go-top').css({'left':'auto'});
}
}
$('#go-top').fadeIn(function(){
$(this).removeClass('dn');
});
}else{
$('#go-top').fadeOut(function(){
$(this).addClass('dn');
});
}
});
$('#go-top .go').on('click',function(){
$('html,body').animate({'scrollTop':0},500);
});
$('#go-top .uc-2vm').hover(function(){
$('#go-top .uc-2vm-pop').removeClass('dn');
},function(){
$('#go-top .uc-2vm-pop').addClass('dn');
});
});
</script>
5、代码整体结构。
6、查看效果。
