var http_request = false;
var sFuncName = 'processDefault';

/**
*=----------------------------------------------------------=
* send_request(url)
*=----------------------------------------------------------=
* 指定处理函数,发送请求的函数
*/
function send_request(url, funcName) {
	initAjax();
	if (typeof(funcName) != 'undefined') {
		sFuncName = funcName;
	}
	http_request.onreadystatechange  = processRequest;
	http_request.open("GET", url, true);
	http_request.send(null);
	//done
}


function send_request_post(url, parameters, funcName) {
	initAjax();
	if (typeof(funcName) != 'undefined') {
		sFuncName = funcName;
	}
	http_request.onreadystatechange = processRequest;
	http_request.open('POST', url, true);
	http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	http_request.setRequestHeader("Content-length", parameters.length);
	http_request.setRequestHeader("Connection", "close");
	http_request.send(parameters);
}


/**
*=----------------------------------------------------------=
* processRequest()
*=----------------------------------------------------------=
*/
function processRequest() {
	if (http_request.readyState == 4) {
		if (http_request.status == 200) {
//			document.getElementById('msg').innerHTML=http_request.responseText;
			eval(sFuncName + '()');
		} else {
			alert("请求的页面有异常");
		}
	}
}

function processDefault() {
	//document.getElementById('ajax_msg').innerHTML=http_request.responseText;
}

/**
 * 初始化
 */
function initAjax() {
	http_request = false;
	if (window.XMLHttpRequest) {
		http_request = new XMLHttpRequest();
		/*
		if(http_request.overrideMimeType) {//设置MIME类别
			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("异常，创建http_request对象实例失败");
		return false;
	}
}