var ajaxRequest = createRequest();
var targetElement;

function createRequest() {
    var myRequest = null;
    if (myRequest) { return myRequest; }
    else {
        req = false;
        if (window.XMLHttpRequest) {
            try { myRequest = new XMLHttpRequest(); return myRequest; }
            catch (e) { myRequest = false; return false; }
            return false;
        } else if (window.ActiveXObject) {
            try { myRequest = new ActiveXObject('Msxml2.XMLHTTP'); return myRequest; }
            catch (e) {
                try { myRequest = new ActiveXObject('Microsoft.XMLHTTP'); return myRequest; } catch (e) { myRequest = false; return false; }
            }
            return false;
        } else { myRequest = false; return false; }
    }
}

function getContent(url, vars, target) {
    targetElement = target;
    showContent("status_loading");
    ajaxRequest.open("POST", url, true);
    ajaxRequest.onreadystatechange = refreshContent;
    ajaxRequest.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
    ajaxRequest.send(vars + "&submit=true");
}

function refreshContent() {
    if (ajaxRequest.readyState == 4) {
        if (ajaxRequest.status == 200) {
            setContent(targetElement, ajaxRequest.responseText);
            showContent(targetElement);
            hideContent("status_loading");
            ajaxRequest = createRequest();         
        }
    }
}

function showContent(target) {   
    document.getElementById(target).style.visibility = 'visible';
}
function hideContent(target) {
    document.getElementById(target).style.visibility = 'hidden';
}
function clearContent(target) {
    document.getElementById(target).innerHTML = '';
}
function setContent(target, value) {
    value = value.replace('<html>','');
    value = value.replace('</html>','');
    document.getElementById(target).innerHTML = value;
}