var xmlHttp

function formatCurrency(num) {
	num = num.toString().replace(/\$|\,/g,'');
	if(isNaN(num))
		num = "0";
	sign = (num == (num = Math.abs(num)));
	num = Math.floor(num*100+0.50000000001);
	cents = num%100;
	num = Math.floor(num/100).toString();
	if(cents<10)
		cents = "0" + cents;
	for (var i = 0; i < Math.floor((num.length-(1+i))/3); i++)
		num = num.substring(0,num.length-(4*i+3))+','+
	num.substring(num.length-(4*i+3));
	return (((sign)?'':'-') + '$' + num + '.' + cents);
}
function calculateTilesAjax()
{
	var is_tiles = document.myForm.is_tiles.checked?true:false;
	var delivery=(document.myForm.delivery[0].checked)?'mail':'download';
	//alert (delivery);
//	if(document.getElementById('mail').checked==true) total_price += 50; // mail delivery options
	//else if(document.getElementById('download').checked==true) total_price += 0;
	var mysql =document.myForm.mysql.checked?'yes':'no';
//	alert(mysql);
	//if(document.getElementById('mysql').checked == true) total_price += 30;
	var zl_from = document.myForm.from.value; //getElementById('from').value;	
	var zl_to = document.myForm.to.value; //getElementById('to').value;
	var shapefile_id = document.myForm.shapefile_id.value; //getElementById('shapefile_id').value;
	var is_hours = document.myForm.is_hours.checked?true:false;
	var hours = document.myForm.num_hours.value;
//	alert (zl_from + ", " + zl_to + ", " + shapefile_id);
xmlHttp=GetXmlHttpObject();
if (xmlHttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  }
var url="script/getTileInfo.php";
url=url+"?is_tiles="+is_tiles;
url=url+"&f="+zl_from;
url=url+"&t="+zl_to;
url=url+"&m="+mysql;
url=url+"&d="+delivery;
url=url+"&s="+shapefile_id;
url=url+"&is_hours="+is_hours;
url=url+"&h="+hours;
xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET",url,true);
xmlHttp.send(null);
}

function stateChanged() 
{ 
if (xmlHttp.readyState==4)
{
var xmlDoc=xmlHttp.responseXML.documentElement;
document.getElementById("num_tiles").innerHTML=xmlDoc.getElementsByTagName("num-tiles")[0].childNodes[0].nodeValue;
var price =  xmlDoc.getElementsByTagName("total-price")[0].childNodes[0].nodeValue;
document.getElementById("price_disp").innerHTML=formatCurrency(price);
//alert(xmlHttp.responseText);
//document.getElementById("ajaxData").innerHTML='';
}
}

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;
}