ie ff js 对象.filters[0].Apply(); 兼容性有关问题

ie ff js 对象.filters[0].Apply(); 兼容性问题？
function display(a)
{
document.getElementById(a).className="selected";
}
function hide(a)
{
document.getElementById(a).className="";
}
function displayList(ulID,index)
{
  var UlObj=document.getElementById(ulID);
  if(UlObj!=null)
  {
  var liList = UlObj.getElementsByTagName("li");
  for (var n=0;n<liList.length;n++)
{
if(n==index)
liList[n].className="selected";
else
liList[n].className="noselected";
}
  }
}
function hideList(a)
{
document.getElementById("List"+a).className="noselected";
}
function displayList1(a)
{
for (var n=11;n<21;n++)
{
document.getElementById("List"+n).className="noselected";
}
document.getElementById("List"+a).className="selected";
}
function hideList1(a)
{
document.getElementById("List"+a).className="noselected";
}

var currslid = 0;
  var slidint;
  var picarry = {};
  var txtarry = {};
  function $(id) { return document.getElementById(id); }
   
  function setfoc(id){
  if(!$('ifocus')) return false;
  var iFocusBtns = $('ifocus_btn').getElementsByTagName('li');
  var FocImg=$('ctl00_main_focpic');
  var iFocusTxs = $('ctl00_main_ifocus_tx');
  for(i=0;i<iFocusBtns.length;i++){
iFocusBtns[i].className = "normal";
  };
   
  FocImg.src = picarry[id];
  currslid = id;
   
  iFocusBtns[id].className ="current";
  FocImg.style.visibility = "hidden";
   
  //FocImg.filters[0].Apply(); //ff no
 
   
  if (FocImg.style.visibility == "visible") {
FocImg.style.visibility = "hidden";
FocImg.filters.revealTrans.transition=23;
  }
  else {
FocImg.style.visibility = "visible";
 
// FocImg.filters[0].transition=23; //ff no
  }
   
  //FocImg.filters[0].Play(); //ff no
   
  iFocusTxs.innerHTML=txtarry[id];
  stopit();
  }

  function playnext(){
if(currslid==3){
currslid = 0;
}
else{
currslid++;
};
setfoc(currslid);
playit();
  }
  function playit(){
setTimeout(playnext,10000);
  }
  function stopit(){
slidint =clearTimeout(slidint);
}
  window.onload = function(){
playit();
  }



//ff no 表示火狐不能运行 请各路朋友帮忙解决下 在些谢过了

------解决方案--------------------
filters[0] 这个事滤镜吗？？？FF不支持 哦 亲
------解决方案--------------------
判断ie的话可以
if(document.body.attachEvent){

}
FF不支持滤镜 放弃吧 亲 哈
------解决方案--------------------
换透明滤镜吧。。参考这个javascript图片卷帘/淡入淡出效果
------解决方案--------------------
哥 2012年了 还用原生js写？现在js框架满天飞，兼容性都帮你做好了，可以考虑入手jquery