var xmlHttp;
function createXMLHttpRequest(){
	if(window.ActiveXObject){
		xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
	}else if(window.XMLHttpRequest){
		xmlHttp = new XMLHttpRequest();
	}
}
function startRequest(url){
	createXMLHttpRequest();
	xmlHttp.onreadystatechange = handleStateChange;
	xmlHttp.open("GET",url,true);
	xmlHttp.send(null);
}
function handleStateChange(){
	if(xmlHttp.readyState == 4){
		if(xmlHttp.status == 200){
			var xmlDoc=xmlHttp.responseXML;//.documentElement;
			var citys=xmlDoc.getElementsByTagName("city");
			var months=xmlDoc.getElementsByTagName("month");
			var days=xmlDoc.getElementsByTagName("day");
			var frm = document.reg_form;
			var option = null;
			if(citys.length!=0){
				var select_city = frm.elements['examcity'];
				select_city.options.length=0;
				for(var i=0;i<citys.length;i++){
				 	var xcode=citys[i].childNodes[0].firstChild.nodeValue;
				 	var xname=citys[i].childNodes[1].firstChild.nodeValue;
				 	var xnamee=citys[i].childNodes[2].firstChild.nodeValue;
				 	option=new Option(unescape(xnamee),unescape(xcode));
				 	//option=new Option(xname,xcode);
				 	try{
				 		select_city.options[select_city.options.length]= option;
				 		option = null;
				 	}catch(e){}
				}
			}
			if(months.length!=0 && days.length==1){
				var select_month = frm.elements['month'];
				select_month.options.length=0;
				//select_month.add(new Option('ÇëÑ¡ÔñÔÂ',''));
				for(var i=0;i<months.length;i++){
					var xcode=months[i].firstChild.nodeValue;
					option=new Option(unescape(xcode),unescape(xcode));
					try{
				 		select_month.options[select_month.options.length]= option;
				 		option = null;
				 	}catch(e){}
				}
			}
			if(days.length!=0){
				var select_day = frm.elements['day'];
				select_day.options.length=0;
				for(var i=0;i<days.length;i++){
					var xcode=days[i].firstChild.nodeValue;
					option=new Option(unescape(xcode),unescape(xcode));
					try{
				 		select_day.options[select_day.options.length]= option;
				 		option = null;
				 	}catch(e){}
				}
			}
		}
	}
}

/***	load the options of select object	***/
function loadOptions(url,frm,obj){
	createXMLHttpRequest();
	xmlHttp.onreadystatechange = function(){
		if(xmlHttp.readyState == 4){
			if(xmlHttp.status == 200){
				var xmlDoc=xmlHttp.responseXML;
				var months=xmlDoc.getElementsByTagName("month");
				var days=xmlDoc.getElementsByTagName("day");
				var option = null;
				if(months.length > 0 && days.length == 1){
					var select_month = frm.elements['smonth'];
					select_month.options.length=0;
					for(var i=0;i<months.length;i++){
						var xcode=months[i].firstChild.nodeValue;
						option=new Option(unescape(xcode),unescape(xcode));
						try{
				 			select_month.options[select_month.options.length]= option;
				 			option = null;
				 		}catch(e){}
					}
				}
				if(days.length > 0){
					var select_day = frm.elements['sday'];
					select_day.options.length=0;
					for(var i=0;i<days.length;i++){
						var xcode=days[i].firstChild.nodeValue;
						option=new Option(unescape(xcode),unescape(xcode));
						try{
				 			select_day.options[select_day.options.length]= option;
				 			option = null;
				 		}catch(e){}
					}
				}
			}
		}
	};
	xmlHttp.open("GET",url,true);
	xmlHttp.send(null);
}

function callback(){
	if(xmlHttp.readyState == 4){
		if(xmlHttp.status == 200){
			var xmlDoc=xmlHttp.responseXML;
			var option = null;
			// do something here.
		}
	}
}
/*******************************************/