function LoadMobs(dung){

    var xhr;
    if (window.XMLHttpRequest) {
        xhr = new XMLHttpRequest();
    } else if (window.ActiveXObject) {
        xhr = new ActiveXObject("Msxml2.XMLHTTP");
    } else {
        throw new Error("Ajax is not supported by this browser");
    }

    xhr.onreadystatechange = function () {
        if (xhr.readyState === 4) {
            if (xhr.status == 200 && xhr.status < 300) {
                // get mobs from PHP
                setTempMobs(JSON.parse(xhr.responseText));
                alert(tmpMs[0].NAME);
            }
        }
    }

    xhr.open('POST', 'loadmobs.php');
    xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
    xhr.send("dung=" + dung);

}

function setTempMobs(mss){
    tmpMs = mss;
}

LoadMobs(currDungBgIndex);
alert(tmpMs[0].NAME);