function getXMLHTTPRequest ()
{
	var req = false;
	try
	{
		req = new XMLHttpRequest ();
	}
	catch (err)
	{
		try
		{
			req = new ActiveXObject ("Msxml2.XMLHTTP");
		}
		catch (err)
		{
			try
			{
				req = new ActiveXObject ("Microsoft.XMLHTTP");
			}
			catch (err)
			{
				req = false;
			}
		}
	}
	return req;
}

function mache_ugr(gr,sub)
{
	var theURL = "tertel_get_ugrs.php?gruppe=" + gr+"&"+"sub="+sub;
	myReq.open ("GET", theURL, true);
	myReq.onreadystatechange = ugrHTTPResponse;
	myReq.send (null);
}


function hole_gr_artikel(gruppe,unter,sub)
{
	var theURL = "tertel_get_gr_artikel.php?gruppe=" + gruppe;
	if (unter) theURL+="&"+"unter="+unter;
	if (sub) theURL+="&"+"sub="+sub;

	myReq.open ("GET", theURL, true);
	myReq.onreadystatechange = artResponse;
	myReq.send (null);
}


function ugrHTTPResponse ()
{
	var optionString, projects, project, projectForm;
	projectForm = document.getElementById ("art");
	
	if ((myReq.readyState == 4) && (myReq.status == 200))
	{
		var subs=myReq.responseXML.getElementsByTagName ("sub");
		var sub=subs[0].childNodes[0].nodeValue;
		var vons=myReq.responseXML.getElementsByTagName ("von");
		var von=vons[0].childNodes[0].nodeValue;
		
		
		if (sub==0)
		{	
			projects = myReq.responseXML.getElementsByTagName ("ugruppe");
			projectForm.unter.options.length = 0;			
			
			for (i = 0; i < myReq.responseXML.getElementsByTagName ("ugruppe").length; i++)
			{
				project = projects[i].childNodes[0].nodeValue;
				erg=project.split(';');
				projectForm.unter.options[i] = new Option (erg[0],erg[1]);
			}  // Ende for (i = 0...
		}	 // Ende if (sub==0)
				
		projects = myReq.responseXML.getElementsByTagName ("sgruppe");
		projectForm.sub.options.length = 0;
		for (i = 0; i < myReq.responseXML.getElementsByTagName ("sgruppe").length; i++)
		{
			project = projects[i].childNodes[0].nodeValue;
			erg=project.split(';');
			projectForm.sub.options[i] = new Option (erg[0], erg[1]);
		}
	}  //Ende if ((myReq.readyState ==
}


function suchtest()
{
		if ((document.getElementById("a_bez").checked ||
		 document.getElementById("a_bes").checked ||
		 document.getElementById("a_inf").checked ||
		 document.getElementById("a_aus").checked) &&
		 document.getElementById("a_suche").value!='')
		{
			document.getElementById("a_sen").disabled=false;
		}
		else
		{
			document.getElementById("a_sen").disabled=true;
		}

}