// HTTP-Objekt erzeugen
var http = getHTTPObject(); 

// Pfad zu php-Skript
var url = "suche.cgi?";

// zeigeErgebnis() wird nur ausgeführt wenn isWorking = false
var isWorking = false;

function handleHttpResponse() {
    // 4 -> HTTP fertig
    if (http.readyState == 4) {
	 document.getElementById("inhalt").innerHTML = http.responseText;
	 isWorking = false;
    }
}

function zeige_ergebnis() {
    //alert("lala");
    if(!isWorking) {
	var such = document.getElementById("suche").value + "+" + document.getElementById("kat").value;
	http.open("GET", url + such, true);
	http.onreadystatechange = handleHttpResponse;
	http.send(null);
	isWorking = true;
    }
}


// erzeugt XMLHttpRequest-Objekt
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;
}