var http_request = false;

//GET method
function send_request(url) {
	http_request = false;
	if(window.XMLHttpRequest) {//Mozilla
		http_request = new XMLHttpRequest();
		if (http_request.overrideMimeType) {
			http_request.overrideMimeType("text/xml");
		}
	}else if (window.ActiveXObject) {//IE
		try {
			http_request = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try {
				http_request = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e) {
			}			
		}
	}
	if (!http_request) {
		window.alert("create XMLHttpRequest error");
		return false;
	}
	http_request.onreadystatechange = processRequest;
	http_request.open("GET",url,true);
	http_request.send(null);
}

//POST method
function post_request(url,arg) {
	http_request = false;
	if(window.XMLHttpRequest) {//Mozilla
		http_request = new XMLHttpRequest();
		if (http_request.overrideMimeType) {
			http_request.overrideMimeType("text/xml");
		}
	}else if (window.ActiveXObject) {//IE
		try {
			http_request = new ActiveXObject("Msxml2.XMLHTTP");
		} catch (e) {
			try {
				http_request = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e) {
			}
		}
	}
	if (!http_request) {
		window.alert("create XMLHttpRequest error");
		return false;
	}
	http_request.onreadystatechange = processRequest;
	http_request.open("POST",url,true);
	http_request.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
	http_request.send(arg);
}

function processRequest() {
	if (http_request.readyState == 4) {
		if (http_request.status == 200) {
			alert(http_request.responseText);
		} else {
			alert("request page error!");
		}
	}
}