function popup(theURL,winName,features,myWidth,myHeight) {  
       var myLeft = (screen.width-myWidth)/2;
       var myTop = (screen.height-myHeight)/2;
       features+=(features!='')?',':'';
       features+=',left='+myLeft+',top='+myTop;
     window.open(theURL,winName,features+((features!='')?',':'')+'width='+myWidth+',height='+myHeight);
}

function unterkategorie(id) {
document.getElementById('u1').style.display = 'none';
document.getElementById('u1').name = '0';
document.getElementById('u2').style.display = 'none';
document.getElementById('u2').name = '0';
 if(id){
    document.getElementById(id).style.display = 'inline';
    document.getElementById(id).name = 'unterkategorie';
 }
}

var url = "inc/kurs_auswahl.php?id=";
function updateAuswahl(id) {
   http.open("GET", url + id, true);
   http.send(null);
}

function getHTTPObject() {
  var xmlhttp;
  /*@cc_on
  @if (@_jscript_version >= 5) try {
  xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
  } catch (e) {
  try {
  xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
  } catch (E){
  xmlhttp = false;
  }
  } @else xmlhttp = false; @end @*/ 
  if (!xmlhttp && typeof XMLHttpRequest != 'undefined') {
  try { xmlhttp = new XMLHttpRequest();
  } catch (e) {
  xmlhttp = false;
  }
  }
  return xmlhttp;
  } var http = getHTTPObject();