运行效果如下：
代码如下：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>JS按钮控制内容上下滚动</title> <style> *{ padding: 0; margin: 0;} li{ list-style: none;} a{ text-decoration: none; color: #333;} a:hover{ color: #f00;} .center{ text-align: center; margin-top: 20px; font-family: "Microsoft Yahei";} #box{ width: 168px; margin: 20px auto; border: 1px solid #ccc; background: #fff; font-size: 12px; position: relative;} #up ,#down{ position: absolute; z-index: 2; cursor: pointer; background: #eee; width: 100%; text-align: center; height: 28px; line-height: 28px;} #up{ top: 0;} #down{ bottom: 0;} .content{ margin-top: 28px; height: 475px; overflow: hidden; position: relative; background: #ccc;} #wrap{ position: absolute; top: 0;} #wrap ul{ padding: 0 10px;} #wrap li{ width: 148px; height: 100px; background: purple; margin-top: 10px;} </style> </head> <body> <h3 class="center">先向上滚动试试，然后向下滚动试试</h3> <div id="box"> <a id="up" href="javascript:;">向上滚动</a> <a id="down" href="javascript:;">向下滚动</a> <div class="content"> <div id="wrap"> <ul> <li></li> <li></li> <li></li> <li></li> <li></li> <li></li> </ul> </div> </div> </div> <script> // 封装getStyle函数 function getStyle(obj ,attr){ return obj.currentStyle ? obj.currentStyle[attr] :getComputedStyle(obj ,false)[attr]; } window.onload = function(){ var oBox = document.getElementById('box'); // alert(getStyle(oBox,'width')) // 168px var oUp = document.getElementById('up'); var oDown = document.getElementById('down'); var oWrap = document.getElementById('wrap'); var num = 0; var timer = null; // 鼠标按下向上链接，开启定时器 oUp.onmousedown = function(){ oWrap.timer = setInterval(function(){ // 先获取内容的top值[获取的是字符串，所以要用parseInt转换成数字]，然后让它每隔300ms减少5px使之向上运动 var dis = parseInt(getStyle(oWrap,'top')) - 5; // 这里的200是根据当前案例设置的，可以根据实际情况调整数值 if( dis < -220){ dis = -220; } oWrap.style.top = dis + 'px'; },30); }; // 鼠标移开向上链接，关闭定时器 oUp.onmouseup = function(){ clearInterval(oWrap.timer); }; // 鼠标按下向下链接，开启定时器 oDown.onmousedown = function(){ oWrap.timer = setInterval(function(){ var dis = parseInt(getStyle(oWrap,'top')) + 5; if(dis > 0){ dis = 0; } oWrap.style.top = dis + 'px'; },30); }; // 鼠标移开向下链接，关闭定时器 oDown.onmouseup = function(){ clearInterval(oWrap.timer); }; }; </script> </body> </html>