这里演示网页上用的滚动条效果，是一个自定义的滚动条代码，除了上下两个箭头以外，滚动条和一般的浏览器基本差不多，鼠标滚轮滚动，滚动条滚动。html结构很简单，mainBox是外层div，content是内容，滚动条div是js动态生成的。
运行效果截图如下：
在线演示地址如下：
具体代码如下：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>滚动条</title> <style type="text/css"> *{ margin:0; padding:0;} p{ height:1000px;} #mainBox{ width:400px; height:500px; border:1px #bbb solid; position:relative; overflow:hidden; margin:50px auto;} #content{ height:2500px; position:absolute; left:0; top:0; background:url(//img.jbzj.com/file_images/article/201510/20151026113716032.jpg) } .scrollDiv{ width:18px; position:absolute; top:0; background:#666; border-radius:10px;} </style> </head> <body> <div> <div></div> </div> <p></p> <script type="text/javascript"> var doc=document; var _wheelData=-1; var mainBox=doc.getElementById('mainBox'); function bind(obj,type,handler){ var node=typeof obj=="string"?$(obj):obj; if(node.addEventListener){ node.addEventListener(type,handler,false); }else if(node.attachEvent){ node.attachEvent('on'+type,handler); }else{ node['on'+type]=handler; } } function mouseWheel(obj,handler){ var node=typeof obj=="string"?$(obj):obj; bind(node,'mousewheel',function(event){ var data=-getWheelData(event); handler(data); if(document.all){ window.event.returnValue=false; }else{ event.preventDefault(); } }); //火狐 bind(node,'DOMMouseScroll',function(event){ var data=getWheelData(event); handler(data); event.preventDefault(); }); function getWheelData(event){ var e=event||window.event; return e.wheelDelta?e.wheelDelta:e.detail*40; } } function addScroll(){ this.init.apply(this,arguments); } addScroll.prototype={ init:function(mainBox,contentBox,className){ var mainBox=doc.getElementById(mainBox); var contentBox=doc.getElementById(contentBox); var scrollDiv=this._createScroll(mainBox,className); this._resizeScorll(scrollDiv,mainBox,contentBox); this._tragScroll(scrollDiv,mainBox,contentBox); this._wheelChange(scrollDiv,mainBox,contentBox); this._clickScroll(scrollDiv,mainBox,contentBox); }, //创建滚动条 _createScroll:function(mainBox,className){ var _scrollBox=doc.createElement('div') var _scroll=doc.createElement('div'); var span=doc.createElement('span'); _scrollBox.appendChild(_scroll); _scroll.appendChild(span); _scroll.className=className; mainBox.appendChild(_scrollBox); return _scroll; }, //调整滚动条 _resizeScorll:function(element,mainBox,contentBox){ var p=element.parentNode; var conHeight=contentBox.offsetHeight; var _width=mainBox.clientWidth; var _height=mainBox.clientHeight; var _scrollWidth=element.offsetWidth; var _left=_width-_scrollWidth; p.style.width=_scrollWidth+"px"; p.style.height=_height+"px"; p.style.left=_left+"px"; p.style.position="absolute"; p.style.background="#ccc"; contentBox.style.width=(mainBox.offsetWidth-_scrollWidth)+"px"; var _scrollHeight=parseInt(_height*(_height/conHeight)); if(_scrollHeight>=mainBox.clientHeight){ element.parentNode.style.display="none"; } element.style.height=_scrollHeight+"px"; }, //拖动滚动条 _tragScroll:function(element,mainBox,contentBox){ var mainHeight=mainBox.clientHeight; element.onmousedown=function(event){ var _this=this; var _scrollTop=element.offsetTop; var e=event||window.event; var top=e.clientY; //this.onmousemove=scrollGo; document.onmousemove=scrollGo; document.onmouseup=function(event){ this.onmousemove=null; } function scrollGo(event){ var e=event||window.event; var _top=e.clientY; var _t=_top-top+_scrollTop; if(_t>(mainHeight-element.offsetHeight)){ _t=mainHeight-element.offsetHeight; } if(_t<=0){ _t=0; } element.style.top=_t+"px"; contentBox.style.top=-_t*(contentBox.offsetHeight/mainBox.offsetHeight)+"px"; _wheelData=_t; } } element.onmouseover=function(){ this.style.background="#444"; } element.onmouseout=function(){ this.style.background="#666"; } }, //鼠标滚轮滚动，滚动条滚动 _wheelChange:function(element,mainBox,contentBox){ var node=typeof mainBox=="string"?$(mainBox):mainBox; var flag=0,rate=0,wheelFlag=0; if(node){ mouseWheel(node,function(data){ wheelFlag+=data; if(_wheelData>=0){ flag=_wheelData; element.style.top=flag+"px"; wheelFlag=_wheelData*12; _wheelData=-1; }else{ flag=wheelFlag/12; } if(flag<=0){ flag=0; wheelFlag=0; } if(flag>=(mainBox.offsetHeight-element.offsetHeight)){ flag=(mainBox.clientHeight-element.offsetHeight); wheelFlag=(mainBox.clientHeight-element.offsetHeight)*12; } element.style.top=flag+"px"; contentBox.style.top=-flag*(contentBox.offsetHeight/mainBox.offsetHeight)+"px"; }); } }, _clickScroll:function(element,mainBox,contentBox){ var p=element.parentNode; p.onclick=function(event){ var e=event||window.event; var t=e.target||e.srcElement; var sTop=document.documentElement.scrollTop>0?document.documentElement.scrollTop:document.body.scrollTop; var top=mainBox.offsetTop; var _top=e.clientY+sTop-top-element.offsetHeight/2; if(_top<=0){ _top=0; } if(_top>=(mainBox.clientHeight-element.offsetHeight)){ _top=mainBox.clientHeight-element.offsetHeight; } if(t!=element){ element.style.top=_top+"px"; contentBox.style.top=-_top*(contentBox.offsetHeight/mainBox.offsetHeight)+"px"; _wheelData=_top; } } } } new addScroll('mainBox','content','scrollDiv'); </script> </body> </html>