此实例通过对滚轮事件的监听，通过滚轮控制滚动条的上下移动，可以将其修改后运用与使用滚轮缩放图片、改变透明度等特效。
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title></title> <style type="text/css"> *{ margin: 0; padding: 0; } #boxwrap{ position: relative; width: 15px; height: 500px; margin: 50px auto; box-sizing: border-box; border: 1px solid gainsboro; border-radius: 6px; } #box{ position: absolute; left: 0px; top: 0px; width: 13px; height: 30px; background: gray; border-radius: 6px; } </style> <script type="text/javascript"> window.onload = function (){ var boxwrp = document.getElementById('boxwrap'); var box = document.getElementById('box'); //兼容firefox if(boxwrp.addEventListener){ document.addEventListener("DOMMouseScroll", fn, false); } document.onmousewheel = fn;//兼容IE、chrome function fn(ev){ var ev = ev||event; var bool = false; //IE、chrome 向上：120，向下：-120 if(ev.wheelDelta){ bool= ev.wheelDelta > 0? true : false; } //firefox 向上：-3，向下：3 else{ bool= ev.detail < 0? true : false; } if(bool){ if(box.offsetTop>=10){ box.style.top = box.offsetTop - 10 + "px"; } else{ box.style.top = 0; } } else{ if(box.offsetTop<=boxwrp.offsetHeight-box.offsetHeight-10){ box.style.top = box.offsetTop + 10 + "px"; } else{ box.style.top = boxwrp.offsetHeight - box.offsetHeight + "px"; } } } } </script> </head> <body> <div> <div></div> </div> </body> </html>