var http_request=false;
var x=0;
function send_request(url,method,sendmode){
	http_request=false;
	if(window.XMLHttpRequest){
		http_request=new XMLHttpRequest();
		if(http_request.overrideMimeType){
			http_request.overrideMimeType("text/xml");
		}
	}
	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){
		window.alert("error!");
		return false;
	}
	switch(method){
		case 1:	http_request.onreadystatechange = processRequest1;break;
		case 2:	http_request.onreadystatechange = processRequest2;break;
	}
	if(sendmode="get"){
		http_request.open("GET",url,true);
		http_request.send(null);
	}else{
		http_request.open("POST",url.split("?")[0],true);
		http_request.setRequestHeader("Content-Type","application/x-www-form-urlencoded;");
		http_request.send(url.split("?")[1]);
	}
}

function processRequest1(){
	if(http_request.readyState==4){
		if(http_request.status==200){
			addOptionGroup("mode",http_request.responseText);
		}else{
			alert("error");
		}
	}
}

function processRequest2(){
	if(http_request.readyState==4){
		if(http_request.status==200){
			addOptionGroup("city",http_request.responseText);
		}else{
			alert("error");
		}
	}
}


function ShowBrand(makeid){
	send_request("show_brand.aspx?makeid="+escape(makeid),1,"get");
}

function ShowCity(ProvinceId){
	send_request("show_city.aspx?provinceId="+escape(ProvinceId),2,"get");
}

function addOption(objSelectNow,txt,val){
	var objOption = document.createElement("OPTION");
	objOption.text= txt;
	objOption.value=val;
	objSelectNow.options.add(objOption);
}
function addOptionGroup(selectId,optGroupString){
	var optGroup = optGroupString.split(",");
	var objSelect = document.getElementsByTagName("SELECT");
	var objSelectNow = objSelect[selectId];
	objSelectNow.length = 1;
	
	//document.all.CityId.options.remove(0); 
	
	for (i=0; i<optGroup.length-1; i++){
		addOption(objSelectNow, optGroup[i], optGroup[i]);
	}
}