var xmlHttp

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;

}

function getbusrates(theform){
	
	var plan = theform.plan.options[theform.plan.selectedIndex].value
	var zone = theform.zone.options[theform.zone.selectedIndex].value
	var trip = theform.trip.options[theform.trip.selectedIndex].value
	var children = theform.children.options[theform.children.selectedIndex].value
	var recuryesno = theform.recuryesno.options[theform.recuryesno.selectedIndex].value
	
	xmlHttp = GetXmlHttpObject()
	
	if(xmlHttp == null){
		alert ("Your browser does not support AJAX!");
		return;
	  }
	
	xmlHttp.onreadystatechange = function(){
			
		if (xmlHttp.readyState == 4){ 
			
			var response = xmlHttp.responseText;
			
			var busrateslist = document.getElementById('busrates_list');
			busrateslist.innerHTML = response;
			var busrateslista = document.getElementById('newrate');
			new Effect.Highlight(busrateslista,{duration: 1.5});
			document.getElementById('busrate_submit').innerHTML='Update Bus Rate';
		}
	}
	
	var url = "inc/busrates_process.php";
	var params = "zone="+zone+"&trip="+trip+"&children="+children+"&plan="+plan+"&recuryesno="+recuryesno;
	
	xmlHttp.open("POST",url,true);
	xmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	xmlHttp.setRequestHeader("Content-length", params.length);
	xmlHttp.setRequestHeader("Connection", "close");
	xmlHttp.send(params);
 
}