仿淘宝网返右下角回顶部按钮效果，只有超过屏幕高度之后才会弹出，用户体验良好，兼容当前主流浏览器。
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<title>兼容多种浏览器右下角返回顶部按钮_武鸣人</title>
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controlHTML: '<img src="/img/20240319_www_wuming_ren_12.png" style="width:24px; height:24px" />', //HTML for control, which is auto wrapped in DIV w/ ID="topcontrol"
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anchorkeyword: '#top', //Enter href value of HTML anchors on the page that should also act as "Scroll Up" links
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jQuery(document).ready(function($){
var mainobj=scrolltotop
var iebrws=document.all
mainobj.cssfixedsupport=!iebrws || iebrws && document.compatMode=="CSS1Compat" && window.XMLHttpRequest //not IE or IE7+ browsers in standards mode
mainobj.$body=(window.opera)? (document.compatMode=="CSS1Compat"? $('html') : $('body')) : $('html,body')
mainobj.$control=$('<div id="topcontrol">'+mainobj.controlHTML+'</div>')
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mainobj.togglecontrol()
$('a[href="' + mainobj.anchorkeyword +'"]').click(function(){
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$(window).bind('scroll resize', function(e){
mainobj.togglecontrol()
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}
}//武鸣人网站https://www.wuming.ren 网站很好记住，wuming.ren(武鸣拼音.ren域名后缀)
scrolltotop.init()
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<a href="https://www.wuming.ren">武鸣人</a>，各种信息资源免费发布，分享励志语录经典短句，减肥健身常识，各种js特效代码。网站很好记住，wuming.ren(武鸣拼音.ren域名后缀)<hr>
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