var req;

function hide() {
    for(var i=0; i<arguments.length; i++) {
        element = document.getElementById(arguments[i]);
        if (element) {
            element.style.visibility = 'hidden';
        }
    }
}

function show() {
    for(var i=0; i<arguments.length; i++) {
        element = document.getElementById(arguments[i]);
        if (element) {
            element.style.visibility = 'visible';
        }
    }
}

function loadXMLDoc(url) {
    if (window.XMLHttpRequest) {
        req = new XMLHttpRequest();
        req.onreadystatechange = processReqChange;
        req.open("GET", url, true);
        req.send(null);

        hide('lastposts');
        show('lastposts_update');

    } else if (window.ActiveXObject) {
        req = new ActiveXObject("Microsoft.XMLHTTP");
        if (req) {
            req.onreadystatechange = processReqChange;
            req.open("GET", url, true);
            req.send();

            hide('lastposts');
            show('lastposts_update');
        }
    }
}

function processReqChange() {
    if (req.readyState == 4) {
        element = document.getElementById('lastposts_text');
        if (element) {
            if (req.status == 200) {
                element.innerHTML = req.responseText;
            } else {
                element.innerHTML = "Error " + req.status + "<br />" + req.statusText;
            }
        }

        hide('lastposts_update');
        show('lastposts');
    } else {
        var status_message = new Array(
        "Запрос не инициализирован",
        "Запрос создан",
        "Запрос отослан",
        "Запрос обрабатывается"
        );

        element_status = document.getElementById('status');
        if (element_status) {
            element_status.innerHTML = status_message[req.readyState];
        }
    }
}