【求助】JavaScript如何让PNG图片在IE6下面透明
请问下JavaScript如何让PNG图片在IE6下面透明，找过一个CSS的方法，但是可惜只能是指定的图片才会透明，并且支持FF和高版本的IE有点问题！所以就不打算用CSS的了！
哪位朋友有在用的代码请共享一下，并且告诉一下如何调用，在此先谢谢各位了！
补充一下，我在网上找了个“轮播器”代码，要把按钮改成圆形的，想用图片来实现，用GIF不是很现实，希望代码也不会影响到轮播器的JS就好了，麻烦各位了！小弟先谢过
轮播器HTML：
<!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=gb2312" /><title>JavaScript ShowImages</title><link href="css/my.css" rel="stylesheet" type="text/css" /><script src="js/my.js" type="text/javascript"></script></head><body><div class="container" id="idTransformView"> <ul class="slider" id="idSlider"> <li><img src="images/01.jpg"/></li> <li><img src="images/02.jpg"/></li> <li><img src="images/03.jpg"/></li> <li><img src="images/04.jpg"/></li> </ul> <ul class="num" id="idNum"> <li>1</li> <li>2</li> <li>3</li> <li>4</li> </ul></div></body></html>
@charset "utf-8";.container, .container *{margin:0; padding:0;}.container{width:510px; height:240px; overflow:hidden;position:relative;}.slider{position:absolute;}.slider li{ list-style:none;display:inline;}.slider img{ width:510px; height:240px; display:block;}.num{ position:absolute; right:5px; bottom:5px;}.num li{ float: left; color: #FF7300; text-align: center; line-height: 30px; width: 30px; height: 30px; font-family: Arial; font-size: 12px; cursor: pointer; overflow: hidden; /**/ margin: 3px 1px; background-image:url(../images/round1.png);}.num li.on{ /*?*/ color: #fff; line-height: 30px; width: 30px; height: 30px; font-size: 16px; margin: 0 1px; border: 0; background-image:url(../images/round1.png); font-weight: bold;}var $ = function (id) { return "string" == typeof id ? document.getElementById(id) : id;};var Class = { create: function() { return function() { this.initialize.apply(this, arguments); } }}Object.extend = function(destination, source) { for (var property in source) { destination[property] = source[property]; } return destination;}var TransformView = Class.create();TransformView.prototype = { initialize: function(container, slider, parameter, count, options) { if(parameter <= 0 || count <= 0) return; var oContainer = $(container), oSlider = $(slider), oThis = this; this.Index = 0; this._timer = null; this._slider = oSlider; this._parameter = parameter; this._count = count || 0; this._target = 0; this.SetOptions(options); this.Up = !!this.options.Up; this.Step = Math.abs(this.options.Step); this.Time = Math.abs(this.options.Time); this.Auto = !!this.options.Auto; this.Pause = Math.abs(this.options.Pause); this.onStart = this.options.onStart; this.onFinish = this.options.onFinish; oContainer.style.overflow = "hidden"; oContainer.style.position = "relative"; oSlider.style.position = "absolute"; oSlider.style.top = oSlider.style.left = 0; }, SetOptions: function(options) { this.options = { Up: true, Step: 5, Time: 10, Auto: true, Pause: 2000, onStart: function(){}, onFinish: function(){} }; Object.extend(this.options, options || {}); }, //start Start: function() { if(this.Index < 0){ this.Index = this._count - 1; } else if (this.Index >= this._count){ this.Index = 0; } this._target = -1 * this._parameter * this.Index; this.onStart(); this.Move(); }, //move Move: function() { clearTimeout(this._timer); var oThis = this, style = this.Up ? "top" : "left", iNow = parseInt(this._slider.style[style]) || 0, iStep = this.GetStep(this._target, iNow); if (iStep != 0) { this._slider.style[style] = (iNow + iStep) + "px"; this._timer = setTimeout(function(){ oThis.Move(); }, this.Time); } else { this._slider.style[style] = this._target + "px"; this.onFinish(); if (this.Auto) { this._timer = setTimeout(function(){ oThis.Index++; oThis.Start(); }, this.Pause); } } }, //length GetStep: function(iTarget, iNow) { var iStep = (iTarget - iNow) / this.Step; if (iStep == 0) return 0; if (Math.abs(iStep) < 1) return (iStep > 0 ? 1 : -1); return iStep; }, //stop Stop: function(iTarget, iNow) { clearTimeout(this._timer); this._slider.style[this.Up ? "top" : "left"] = this._target + "px"; }};window.onload=function(){ function Each(list, fun){ for (var i = 0, len = list.length; i < len; i++) { fun(list[i], i); } }; var objs = $("idNum").getElementsByTagName("li"); var tv = new TransformView("idTransformView", "idSlider", 240, 4, { onStart : function(){ Each(objs, function(o, i){ o.className = tv.Index == i ? "on" : ""; }) }//Button Style }); tv.Start(); Each(objs, function(o, i){ o.onmouseover = function(){ o.className = "on"; tv.Auto = false; tv.Index = i; tv.Start(); } o.onmouseout = function(){ o.className = ""; tv.Auto = true; tv.Start(); } }) ////////////////////////test2 var objs2 = $("idNum2").getElementsByTagName("li"); var tv2 = new TransformView("idTransformView2", "idSlider2", 408, 3, { onStart: function(){ Each(objs2, function(o, i){ o.className = tv2.Index == i ? "on" : ""; }) },//Button Style Up: false }); tv2.Start(); Each(objs2, function(o, i){ o.onmouseover = function(){ o.className = "on"; tv2.Auto = false; tv2.Index = i; tv2.Start(); } o.onmouseout = function(){ o.className = ""; tv2.Auto = true; tv2.Start(); } }) }