var xmlHttp;

function getCities(str)
{
	if (str.length==0)
	{
		document.getElementById("cities").innerHTML="";
		return;
	}
	xmlHttp=GetXmlHttpObject();
	if (xmlHttp==null)
	{
		alert ("Browser does not support HTTP Request");
		return;
	}
	var url="includes/functions/get_cities.php";
	url=url+"?cid="+str;
	url=url+"&sid="+Math.random();
	xmlHttp.onreadystatechange=stateChanged;
	xmlHttp.open("GET",url,true);
	xmlHttp.send(null);
} 

function stateChanged() 
{ 
	if (xmlHttp.readyState==4 || xmlHttp.readyState=="complete")
	{
		document.getElementById("cities").innerHTML=xmlHttp.responseText;
	}
}

function GetXmlHttpObject()
{
	var xmlHttp=null;
	try
	{
		// Firefox, Opera 8.0+, Safari
		xmlHttp=new XMLHttpRequest();
	}
	catch (e)
	{
		// Internet Explorer
		try
		{
			xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e)
		{
			xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
		}
	}
	return xmlHttp;
}