function getXMLDoc() {
    if(window.XMLHttpRequest) {
        return new XMLHttpRequest();
    } else if (window.ActiveXObject) {
        return new ActiveXObject("Microsoft.XMLHTTP");
    }
}

function getObject(elementID) {
    if (document.getElementById)
        return document.getElementById(elementID);
    else if (document.layers)
        return document.layers[elementID];
    else if (document.all)
        return document.all[elementID];
}

function setform(formtrigger,formfield,formdata,page) {
    if(typeof page=="undefined") {page="";}
    getObject('trigger').name=formtrigger;
    getObject('data').name=formfield;
    getObject('data').value=formdata;
    document.scriptform.action=page;
    document.scriptform.submit();
}

function surfto(page) {
    document.surftoform.action = page;
    document.surftoform.submit();
}

function openhandleiding(pagina) {
    var varwidth = 700;
    var varheight = 600;
    var varleft = (screen.width-varwidth)/2;
    var vartop = (screen.height-varheight)/3;
    window.open('/login_handleiding.php','handleidingeurorefs','width='+varwidth+',height='+varheight+',menubar=no,resizable=yes,status=yes,scrollbars=yes,left='+varleft+',top='+vartop+'');
}

function isInteger(s) {
    if(s=='') return false;
    var valid = '0123456789';
    for(var i=0; i<s.length; i++)
        if(valid.indexOf(s.charAt(i)) < 0) return false;
    return true;
}

function isDecimal(s) {
    if(s=='') return false;
    var valid = '0123456789.';
    for(var i=0; i<s.length; i++)
        if(valid.indexOf(s.charAt(i)) < 0) return false;
    return true;
}