var xmlHttp

function GetXmlHttpObject(handler)
{
    var objXmlHttp=null

    if (navigator.userAgent.indexOf("Opera")>=0)
    {
        alert("AJAX doesn't work in Opera")
        return
    }
    if (navigator.userAgent.indexOf("MSIE")>=0)
    {
        var strName="Msxml2.XMLHTTP"
        if (navigator.appVersion.indexOf("MSIE 5.5")>=0)
        {
            strName="Microsoft.XMLHTTP"
        }

        try
        {
            objXmlHttp=new ActiveXObject(strName)
            objXmlHttp.onreadystatechange=handler
            return objXmlHttp
        }
        catch(e)
        {
            alert("Error. Scripting for ActiveX might be disabled")
            return
        }
    }
    if (navigator.userAgent.indexOf("Mozilla")>=0)
    {
        objXmlHttp=new XMLHttpRequest()
        objXmlHttp.onload=handler
        objXmlHttp.onerror=handler
        return objXmlHttp
    }
}

function createAjaxObj(){
    var httprequest=false
    if (window.XMLHttpRequest){ // if Mozilla, Safari etc
        httprequest=new XMLHttpRequest()
        if (httprequest.overrideMimeType)
        httprequest.overrideMimeType('text/xml')
    }
    else if (window.ActiveXObject){ // if IE
        try {
            httprequest=new ActiveXObject("Msxml2.XMLHTTP");
        }
        catch (e){
            try{
                httprequest=new ActiveXObject("Microsoft.XMLHTTP");
            }
            catch (e){}
        }
    }
    return httprequest
}

var ajaxpack=new Object()
ajaxpack.basedomain="http://"+window.location.hostname
ajaxpack.ajaxobj=createAjaxObj()
ajaxpack.filetype="txt"
ajaxpack.addrandomnumber=0 //Set to 1 or 0. See documentation.

ajaxpack.getAjaxRequest=function(url, parameters, callbackfunc, filetype){
    ajaxpack.ajaxobj=createAjaxObj() //recreate ajax object to defeat cache problem in IE
    if (ajaxpack.addrandomnumber==1) //Further defeat caching problem in IE?
    var parameters=parameters+"&ajaxcachebust="+new Date().getTime()
    if (this.ajaxobj){
        this.filetype=filetype
        this.ajaxobj.onreadystatechange=callbackfunc
        this.ajaxobj.open('GET', url+"?"+parameters, true)
        this.ajaxobj.send(null)
    }
}

ajaxpack.postAjaxRequest=function(url, parameters, callbackfunc, filetype){
    ajaxpack.ajaxobj=createAjaxObj() //recreate ajax object to defeat cache problem in IE
    if (this.ajaxobj){
        this.filetype=filetype
        this.ajaxobj.onreadystatechange = callbackfunc;
        this.ajaxobj.open('POST', url, true);
        this.ajaxobj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        this.ajaxobj.setRequestHeader("Content-length", parameters.length);
        this.ajaxobj.setRequestHeader("Connection", "close");
        this.ajaxobj.send(parameters);
    }
}