var currentPos = null;
var http_request = false; 
function send_request(url) 
{
	//初始化、指定处理函数、发送请求的函数
	http_request = false;
	//开始初始化XMLHttpRequest对象
	if(window.XMLHttpRequest)
	{ //Mozilla 浏览器
		http_request = new XMLHttpRequest();
		if (http_request.overrideMimeType)
		{//设置MiME类别
			http_request.overrideMimeType('text/xml');
		}
	}
	else if (window.ActiveXObject) 
	{ // IE浏览器
		try 
		{
			http_request = new ActiveXObject("Msxml2.XMLHTTP");
		}
		catch (e) 
		{
			try 
			{
				http_request = new ActiveXObject("Microsoft.XMLHTTP");
			}
			catch (e) 
			{
			}
		}
	}
	if (!http_request)
	{ // 异常，创建对象实例失败
		window.alert("不能创建XMLHttpRequest对象实例.");
		return false;
	}
	http_request.onreadystatechange = processRequest;
	// 确定发送请求的方式和URL以及是否同步执行下段代码
	http_request.open("GET", url, true);
	http_request.send(null);
}
// 处理返回信息的函数
function processRequest() 
{
	// 判断对象状态
	// readyState: 对象状态(integer):0 = 未初始化,1 = 读取中,2 = 已读取,3 = 交互中,4 = 完成
	if (http_request.readyState == 4) 
	{ 			
		// 信息已经成功返回，开始处理信息
		//status : 服务器返回的状态码, 如：404 = "文件末找到" 、200 ="成功"
		if (http_request.status == 200) 
		{ 
			//alert(http_request.responseText);
			document.getElementById(currentPos).innerHTML = http_request.responseText;
			//if (http_request.responseText.indexOf("NoTreeNodes") != -1)
			// {
				//document.getElementById(currentPos).style.display = "none";
			//	}
			
		}
		else 
		{ //页面不正常
			alert("您所请求的页面有异常。");
		}
	}
}
    
function AjaxList(objDivName,requestUrl) 
{
	document.getElementById(objDivName).style.display = "";
	document.getElementById(objDivName).innerHTML = "<img src='images/loading.gif'  hspace='0' vspace='0' border='0'>  <div class='loading' style='display:inline'>载入中...</div>";
	//为document.getElementById(currentPos).innerHTML = http_request.responseText; 作准备
	currentPos = objDivName;
	//调用
	send_request(requestUrl);
}
	
function DelayLoadTree(treeid)
{
    var objDivName = "D" + treeid;
    var div = document.getElementById(objDivName);
	var visible = (div.style.display!="none");
	var key = document.getElementById("P" + treeid);
	if (visible)
	{
		div.style.display="none";	
	 	key.innerHTML="<img src='images/plus.gif'  hspace='0' vspace='0' border='0'>";
	}
	else
	{
		div.style.display="block";
	 	var requestUrl = "hytree.aspx?id="+treeid+"&ft=1";
		//alert(requestUrl);
	 	key.innerHTML="<img src='images/minus.gif'  hspace='0' vspace='0' border='0'>";
		AjaxList(objDivName,requestUrl);
	}
}
  	
function DelayLoadFirstListTree(objDivName,treeid)
{
	var requestUrl = "hytree.aspx?id="+treeid;
	//alert(requestUrl);
	AjaxList(objDivName,requestUrl);
}