var menu

//// update left menu
function loadMenu(str)
{
	menu=GetXmlHttpObject();

	if (menu==null)
	{
		alert ("Your browser does not support AJAX!");
		return;
	}
	
	var menu_url="ajax/leftmenu.php";
		
	menu_url=menu_url+"?"+str;
	menu.onreadystatechange=updateMenu;
	menu.open("GET", menu_url, true);
	menu.send(null);
}

///// replace the content with the generated menu
function updateMenu()
{
	if (menu.readyState==4)
	{
		document.getElementById("leftmenu").innerHTML=menu.responseText;
	}
}

///// send the server request
function GetXmlHttpObject()
{
	if (window.XMLHttpRequest)
	{
		return new XMLHttpRequest();
	}
	
	if (window.ActiveXObject)
	{
		return new ActiveXObject("Microsoft.XMLHTTP");
	}
	
	return null;
}