// Wert eines Input-Feldes löschen

function resetValue(id)
{
	document.getElementById(id).value = "";
}

// PHP-Skript per JavaScript aufrufen

function get(url, callback_function, return_xml)
{
	var http_request = false;

	if (window.XMLHttpRequest)
	{
		http_request = new XMLHttpRequest();
		
		if (http_request.overrideMimeType)
		{
			http_request.overrideMimeType('text/xml; charset= iso-8859-1');
		}
	}
	else if(window.ActiveXObject)
	{
		try
		{
			http_request = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e)
		{
			try
			{
				http_request = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e)
			{
			}
		}
	}
	if (!http_request)
	{
		//alert('Leider unterstützt Ihr Browser diese Funktion nicht.');
		return false;
	}
	http_request.onreadystatechange = function()
	{
		if (http_request.readyState == 4)
		{
			if (http_request.status == 200)
			{
				if (return_xml)
				{
					eval(callback_function + '(http_request.responseXML)');
				}
				else
				{
					eval(callback_function + '(http_request.responseText)');
				}
			}
			else
			{
				//alert('Problem: ' + http_request.status + ')');
			}
		}
	}
	
	http_request.open('GET', url, true);
	http_request.send(null);
}

function doNothing()
{
}