function createXMLHttp()
{
    var xmlhttp=false;
    /*@cc_on @*/
    /*@if (@_jscript_version >= 5)
    // JScript gives us Conditional compilation, we can cope with old IE versions.
    // and security blocked creation of the objects.
     try {
      xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
     } catch (e) {
      try {
       xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
      } catch (E) {
       xmlhttp = false;
      }
     }
    @end @*/
    if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
	    try {
		    xmlhttp = new XMLHttpRequest();
	    } catch (e) {
		    xmlhttp=false;
	    }
    }
    if (!xmlhttp && window.createRequest) {
	    try {
		    xmlhttp = window.createRequest();
	    } catch (e) {
		    xmlhttp=false;
	    }
    }
    return xmlhttp;
}
function genericAjax(url)
{
    var ajaxObj=createXMLHttp();
    //Use this function when no response is needed
    ajaxObj.open("GET", url+'&rand='+Math.random(),true);
    ajaxObj.open("GET", url,true);
    ajaxObj.send(null);
}

//Pass the web service a reference to the function to call when it returns
//Callback must be a function accepting a single argument, which will be the response text
function MakeAjaxCall(url, callback)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("GET", url+'&rand='+Math.random(),true);
    ajaxObj.onreadystatechange=function() {
        if (ajaxObj.readyState==4) {
            callback(ajaxObj.responseText);
        }
    }
    ajaxObj.send(null);
}

//Pass the web service a reference to the function to call when it returns
//Callback must be a function accepting a single argument, which will be the response text
function MakeAjaxPost(url, postData, callback)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("POST", url+'&rand='+Math.random(),true);
    ajaxObj.onreadystatechange=function() {
        if (ajaxObj.readyState==4) {
            callback(ajaxObj.responseText);
        }
    }
    ajaxObj.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
    ajaxObj.send(postData);
}

/* Sets a session variable - callback should expect a simple result code ("0" for success, else "ERROR:[errortext]") 
   Make sure that the value you are setting stringifies nicely, or has been pre-stringified
*/
function SetSessionVariable(url, key, value, callback)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("POST", url+"?cmd=setcookie&rand="+Math.random(),true);
    ajaxObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    ajaxObj.onreadystatechange=function() {
        if (ajaxObj.readyState==4) {
            callback(ajaxObj.responseText);
        }
    }
    ajaxObj.send("key="+key+"&value="+value);
}

/* sets a .NET application variable (global variable) */
function SetApplicationVariable(url, key, value, callback)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("POST", url+"?cmd=setappvar&rand="+Math.random(),true);
    ajaxObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    ajaxObj.onreadystatechange=function() {
        if (ajaxObj.readyState==4) {
            callback(ajaxObj.responseText);
        }
    }
    ajaxObj.send("key="+key+"&value="+value);
}

/*... and gets it back :) */
function GetApplicationVariable(url, key, callback)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("POST", url+"?cmd=getappvar&rand="+Math.random() ,true);
    ajaxObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    ajaxObj.onreadystatechange=function() {
        if (ajaxObj.readyState==4) {
            callback(ajaxObj.responseText);
        }
    }
    ajaxObj.send("key="+key);
}

/*... destroys (sets to null) an application variable */
function KillApplicationVariable(key)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("POST", "/app_info/ajaxendpoint/default.aspx?cmd=killappvar&rand="+Math.random() ,true);
    ajaxObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    ajaxObj.send("key="+key);
}


/* Retrieves a previously set session variable. The callback should expect the string value of the
   cookie if it exists, "null" if it does not, else the standard error format */
function GetSessionVariable(url, key, callback)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("POST", url+"?cmd=getcookie&rand="+Math.random() ,true);
    ajaxObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    ajaxObj.onreadystatechange=function() {
        if (ajaxObj.readyState==4) {
            callback(ajaxObj.responseText);
        }
    }
    ajaxObj.send("key="+key);
}



/* Quickie Validation Methods - Requires that JQuery be loaded and available to call */
/* Error messages should be of class sn_visibleInlineError */

function HideAllErrors()
{
/*
    var $j= jQuery.noConflict();
    $$(".sn_visibleInlineError").each(Element.hide);
*/
}

function ShowAllErrors()
{
    $$(".sn_visibleInlineError").each(Element.show);
}

 //id = ID of error message container
function ShowError(id)
{
    $(id).show();
}
function HideError(id)
{

    $(id).hide();

}



/* UI Methods - Requires that JQuery be loaded and available to call */
function ClearTextFields()
{
    //TODO: write in prototype or regular JS.
}

/* Methods involving "Hanging Gets" (server callbacks) */
function WaitForCondition(url, key, value, callback)
{
    var ajaxObj=createXMLHttp();
    ajaxObj.open("POST", url+"?cmd=RegisterEvent&rand="+Math.random(),true);
    ajaxObj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    ajaxObj.onreadystatechange=function() {
        if (ajaxObj.readyState==4) {
            callback(ajaxObj.responseText);
        }
    }
    ajaxObj.send("key="+key+"&value="+value);
}