var xmlhttp;

function ricarica_disciplina(corso, disciplina)
{
    xmlhttp=getXmlHttpObject();
    if (xmlhttp==null)
    {
        alert ("Il vostro browser non supporta XMLHTTP!\nPrego utilizzare Mozilla Firefox!");
        return;
    }
    var url="script_disciplina_corsi.asp?corso="+corso+"&disciplina="+disciplina;
    xmlhttp.onreadystatechange=stateChanged;
    xmlhttp.open("get",url,true);
    xmlhttp.send(null);
}

function stateChanged()
{
    if (xmlhttp.readyState==4)
    {
        document.getElementById("disciplina").innerHTML=xmlhttp.responseText;
    }
}

function getXmlHttpObject()
{
    if (window.XMLHttpRequest)
    {
    // code for IE7+, Firefox, Chrome, Opera, Safari
        return new XMLHttpRequest();
    }
    if (window.ActiveXObject)
    {
        // code for IE6, IE5
        return new ActiveXObject("Microsoft.XMLHTTP");
    }
    return null;
}