不错，ie,firefox,opera 通通搞定。

</p> <p><script type="text/javascript"></p> <p>function handle(delta) {</p> <p> if (delta < 0)</p> <p> alert("向下滚动");</p> <p> else</p> <p> alert("向上滚动");;</p> <p>}</p> <p>function wheel(event){</p> <p> var delta = 0;</p> <p> if (!event) /* For IE. */</p> <p> event = window.event;</p> <p> if (event.wheelDelta) { /* IE/Opera. */</p> <p> delta = event.wheelDelta/120;</p> <p> /** In Opera 9, delta differs in sign as compared to IE.</p> <p> */</p> <p> if (window.opera)</p> <p> delta = -delta;</p> <p> } else if (event.detail) { /** Mozilla case. */</p> <p> /** In Mozilla, sign of delta is different than in IE.</p> <p> * Also, delta is multiple of 3.</p> <p> */</p> <p> delta = -event.detail/3;</p> <p> }</p> <p> /** If delta is nonzero, handle it.</p> <p> * Basically, delta is now positive if wheel was scrolled up,</p> <p> * and negative, if wheel was scrolled down.</p> <p> */</p> <p> if (delta)</p> <p> handle(delta);</p> <p>}</p> <p>/** Initialization code. </p> <p> * If you use your own event management code, change it as required.</p> <p> */</p> <p>if (window.addEventListener)</p> <p> /** DOMMouseScroll is for mozilla. */</p> <p> window.addEventListener('DOMMouseScroll', wheel, false);</p> <p>/** IE/Opera. */</p> <p>window.onmousewheel = document.onmousewheel = wheel;</p> <p></script></p> <p> [Ctrl+A 全部选择 提示：你可先修改部分代码，再按运行]

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