var http_request;
function send_request(url,fun) {
	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.3.0");
		} catch (e) {
			try {
				http_request = new ActiveXObject("Microsoft.XMLHTTP");
			} catch (e) {}
		}
	}
	if (!http_request) { 

		window.alert("请更新你的IE浏览器");
		return false;
	}
	http_request.onreadystatechange =fun;
	http_request.open("Post", url, true);
	http_request.setRequestHeader("If-Modified-Since", "0");
	http_request.send(null);
}
function get_class_level(id,deepth)
{
	LV = new Array(deepth);
	level = 0
	for(i=0;i<deepth;i++)
	{
		 LV[i] = (id>> 8*(deepth-i-1)) & 0xFF;
		 if(LV[i]>0)
		 	level = i+1;	 
	}
	return level
}
function make_class_level(deepth)
{
	_id = 0;
	len = LV.length;
	for(i=0;i<LV.length;i++)
	{
		if(i<deepth)
		{
			_id += LV[i] << 8*(len-i-1);
			
		}
	}
	return _id;
}
function init()
{
	for(ii=1;ii<=deepth;ii++)
	{
		thread[ii-1] = make_class_level(ii);
		thread_state[thread[ii-1]] =false;
	}
}
function call_back(parent_id)
{
	if (http_request.readyState == 4) 
	{ 
	
		if (http_request.status == 200) 
		{
			
	
		} 
		else { 
			alert("您所请求的页面有异常。");
		}
	}
}
function add_item(id)
{
	document.write("??");
}