雅虎、网易ajax标签导航效果的实现

function getObject(objectId) {
     if(document.getElementById && document.getElementById(objectId)) {
    // W3C DOM
       return document.getElementById(objectId);
     }
     else if (document.all && document.all(objectId)) {
    // MSIE 4 DOM
       return document.all(objectId);
     }
     else if (document.layers && document.layers[objectId]) {
    // NN 4 DOM.. note: this won't find nested layers
       return document.layers[objectId];
     }
     else {
       return false;
    }
}
var responsecont;
var xmlHttp;
var xH=new Object();
var rqtp=new Object();
var dateStr,dStr;
var requestType;
var etype=0;
var newsstring;
var ajccache=new Object();
var url;
var MouseDelayTime=200;//鼠标感应延迟
var waitInterval;
var Browser = new Object();
Browser.isMozilla = (typeof document.implementation != 'undefined') && (typeof document.implementation.createDocument != 'undefined') && (typeof HTMLDocument!='undefined');
Browser.isIE = window.ActiveXObject ? true : false;
Browser.isFirefox = (navigator.userAgent.toLowerCase().indexOf("firefox")!=-1);
Browser.isOpera = (navigator.userAgent.toLowerCase().indexOf("opera")!=-1);
function SetCookie(name,value,expires){//写cookie
var exp=new Date();
exp.setTime(exp.getTime()+expires*60000);
document.cookie=name+"="+escape(value)+";expires="+exp.toGMTString();//+";domain=arkoo.com;path=/";
}
function readcookie(name){//读取cookie
var oRegex=new RegExp(name+'=([^;]+)','i');
var oMatch=oRegex.exec(document.cookie);
if(oMatch&&oMatch.length>1)return unescape(oMatch[1]);
else return '';
}
function CreateXMLHttpRequest(){
   // Initialize Mozilla XMLHttpRequest object
   if (window.XMLHttpRequest){
       xmlHttp = new XMLHttpRequest();
   }
   // Initialize for IE/Windows ActiveX version
   else if (window.ActiveXObject) {
       try{
            xmlHttp = new ActiveXObject("Msxml2.XMLHTTP.3.0");
       }
       catch (e){
            try{
            xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
            }
            catch (e){newsstring = "<div class='loading'>Loading rquest content fail, Please try it again latter...</div>";}
       }
   }
}
function getnews(tagid,x){
url = "tab/"+tagid+'_'+x+'.html';
var url2=url;
requestType = tagid;
if(ajccache[url]==null){
var loadstatustext="<div class='loading'><img src='tab/images/loading.gif' /> Loading request content, please wait...</div>";
rqtp[tagid]=tagid;
CreateXMLHttpRequest();   
var hdr=tagid;
   xH[tagid]=xmlHttp;
   if(etype==1)getObject(requestType+'_cnt').innerHTML = loadstatustext;
   xH[tagid].onreadystatechange = function(){
   // only if xmlHttp shows "complete"
   if (xH[tagid].readyState == 4){
      // only http 200 to process
      if (window.location.href.indexOf("http")==-1 || xH[tagid].status == 200){
         newsstring = xH[tagid].responseText;
    dateStr=xH[tagid].getResponseHeader("Date");
    dStr = new Date(dateStr);SetCookie('dStr',dStr,10000000);
         //inject centent to tab-pane
            shownews(rqtp[tagid],newsstring);
            ajccache[url2]=newsstring;
      }
   }
}
   xH[tagid].open("GET", url, true);
   xH[tagid].setRequestHeader("If-Modified-Since","0");
   xH[tagid].send(null);
}
else
{shownews(requestType,ajccache[url]);}
}
function shownews(requestType,newsstring){
//<![CDATA[
    responsecont = getObject(requestType+'_cnt');
    responsecont.innerHTML = newsstring;
    getObject("pdate").innerHTML=dStr;
if(getObject("alta")){ata(getObject("alta"));hideText();}
//]]>
}
function TabNews(tagid,x){
    var lim=getObject(tagid+"_mn").getElementsByTagName('li');
    var mnt=getObject(tagid+"_mn").getElementsByTagName('li').length;
    if(!mnt)mnt=4;
    for(var i=0;i<mnt;i++){
        if(i == (x-1)){
            if(i==0){
                lim[i].className="tabactive1";
            }
            else{
                lim[i].className="tabactive2";
                lim[i-1].getElementsByTagName('a')[0].style.background="url()";
            }
            lim[i].getElementsByTagName('a')[0].style.background="url(tab/images/tab_bgs.gif) right -60px no-repeat";
            try{getnews(tagid,x);}catch(e){alert(e);}
        }    
        else{
            lim[i].className="";
            lim[i].getElementsByTagName('a')[0].style.background="url(tab/images/tab_bgs.gif) right -88px no-repeat";        
        }
    }
}
var idn,tmpa,tmpat;
var aw="";
var rT;
function aet(tagid,etp){
var lis=getObject(tagid+"_mn").getElementsByTagName('li');
var wts=tagid+"_cnt";
var wnf=tagid+"info";
if(readcookie(tagid+"_cntd")=="none"){
    hiddenList(getObject(wts));
    maxh[wts]=readcookie(tagid+"_cnth");
    getObject("pdate").innerText=readcookie("dStr");
    }
else{
    if(parseInt(readcookie(wnf))>1)
    TabNews(tagid,readcookie(wnf));//返回上次访问
    else
    TabNews(tagid,1);
    if(etp==1)aw=tagid+readcookie(wnf);
}
    for(var iy=0;iy<lis.length;iy++){
        with(lis[iy]){
        if(etp==0){
        lis[iy].onmouseover=function(){
            rT=attributes.getNamedItem('id').value.substring(0, attributes.getNamedItem('id').value.length-1);
            if(getObject(rT+'_cnt').style.display != "none"&&className!="") return;
            idn=parseInt(attributes.getNamedItem('id').value.substring(attributes.getNamedItem('id').value.length-1, attributes.getNamedItem('id').value.length));
            clearTimeout(waitInterval);
            waitInterval=window.setTimeout("etype=0;TabNews(rT,idn);if(getObject(rT+'_cnt').style.display == 'none')displayList(rT+'_cnt'); SetCookie(rT+'info',idn,10000000);SetCookie(rT+'_cntd','ture',10000000);",MouseDelayTime);
            }
        lis[iy].onmouseout=function(){if(getObject(rT+'_cnt').style.display != "none"&&className!="") return;clearTimeout(waitInterval);}
        }
        if(etp==1){
        lis[iy].onmouseover=function(){getElementsByTagName('a')[0].blur();}
        lis[iy].onclick=function(){
            idn=parseInt(attributes.getNamedItem('id').value.substring(attributes.getNamedItem('id').value.length-1, attributes.getNamedItem('id').value.length));
            rT=attributes.getNamedItem('id').value.substring(0, attributes.getNamedItem('id').value.length-1);
            if(getObject(rT+'_cnt').style.display != "none"&&(idn==1&&(this.className=="tabactive1")||aw==attributes.getNamedItem('id').value)) return true;
                if(getObject(rT+'_cnt').style.display == "none"){
                displayList(rT+'_cnt');SetCookie(rT+'_cntd','ture',10000000);
                }
            etype=1;
            TabNews(rT,idn);
            SetCookie(rT+'info',idn,10000000);
            aw=attributes.getNamedItem('id').value;
            getElementsByTagName('a')[0].blur();
            return false;
            }}}
    }
}
function ata(objid){
var as=objid.getElementsByTagName('a');
for(var i=0;i<as.length;i++){
as[i].target="_self";
}
}
function GetUrlParam(paramName){    //获取URL参数的函数
    var oRegex = new RegExp('[\?&]' + paramName + '=([^&]+)', 'i');
    var oMatch = oRegex.exec(window.location.search);
    if(oMatch && oMatch.length > 1)
        return oMatch[1];
    else
        return '';
}
function hideText(){
if(document.getElementsByTagName("arkoo:title").length==0){
var upu=GetUrlParam("username");
var upa=GetUrlParam("articleid");
getObject("closeit").innerHTML='<a href="http://cn.arkoo.com/diaryfiles/showpage.aspx?username='+upu+'&articleid='+upa+'" target="_blank">查看原文</a> <a href="tab.html" target="_self">×</a>';
}
}
var maxh=new Object();
//显示内容框
function displayList(oid){   
    var h = 0;  
    var objid=getObject(oid);
          if(isNaN(parseInt(maxh[oid]))) var max_h = 210; // 容器的最大高度
        else
            var max_h = maxh[oid];
          var anim = function(){            
                    h += 50; // 每次递增50像素
                    if(h >= max_h){
                    objid.style.height = max_h + "px";;
                    getObject('tab'+objid.attributes.getNamedItem('id').value).style.background="url(tab/images/tab_bgs.gif) 5px -113px no-repeat"; // 让图片标签改变背景          
                    if(tt){window.clearInterval(tt);}
                    }
                    else{
                objid.style.display="block";
                objid.style.height = h + "px";
                    }
            }
               
              var tt = window.setInterval(anim,2);      
}
// 隐藏列表框
function hiddenList(objid){
       var h = objid.offsetHeight;
           var anim = function(){
                 h -= 50; // 每次递减50像素
                 if(h <= 5){
                 objid.style.display="none";
                   getObject('tab'+objid.attributes.getNamedItem('id').value).style.background="url(tab/images/tab_bgs.gif) -14px -114px no-repeat";
                   if(tt){window.clearInterval(tt);}
               }
               else{
                   objid.style.height = h + "px";
               }
           }
             
           var tt = window.setInterval(anim,2);
}
function showClassList(oid){
var objid=getObject(oid);
   if(objid.style.display == "none"){
    if(objid.getElementsByTagName("img").length==0)TabNews(oid.substring(0,oid.indexOf("_")),1);
       displayList(oid); // 显示内容框
    SetCookie(oid+'d',"ture",10000000);
   }
   else{
      if(isNaN(parseInt(maxh[oid]))){
         maxh[oid]=objid.offsetHeight; // 内容容器的初始高度
      }
      hiddenList(objid); // 隐藏内容框
    SetCookie(oid+'d',"none",10000000);SetCookie(oid+'h',maxh[oid],10000000);
   }
}