function $(objID) {
  return document.getElementById(objID)
}

function $F(objID) {
  return document.getElementById(objID).value
}
 
var XMLHttp=function(){
	try {return new ActiveXObject("Msxml5.XMLHTTP");}catch(e){}
	try {return new ActiveXObject("Msxml4.XMLHTTP");}catch(e){}
	try {return new ActiveXObject("Msxml3.XMLHTTP");}catch(e){}
	try {return new ActiveXObject("Msxml2.XMLHTTP");}catch(e){}
	try {return new ActiveXObject("Microsoft.XMLHTTP");}catch(e){}
	try {return new XMLHttpRequest();}catch(e){}
	return null;
}

function updater(objid,url,method,parameters,loading,async){
	var req=new XMLHttp();
	var objid=objid;
	var url=url;
	var method=method;
	var parameters=parameters;
	var loading=loading;
	var async=async;
	if (req!=null){
		req.onreadystatechange = function(){
			if (req.readyState==4){
				if(req.status==200){
					window.status=""
					$(loading).style.display="none";
					$(objid).innerHTML=req.responseText;
				}else{
					window.status="服务器出错,错误代码："+req.statusText
					alert("服务器出错,错误代码："+req.statusText)
				}
			}else{
				 window.status="正在加载......"
				 $(loading).style.display="block";
			}
		}
		if (parameters=="") url=url;
		else url+="?"+parameters;
		url+=(url.indexOf("?") >= 0)?"&nowtime="+new Date().getTime():"?nowtime=" + new Date().getTime();
		if (method=='get'){
			req.open('GET',url,async);
			req.send(null);
		}else if (method=='post'){
			req.open('POST',url,async);
			req.setRequestHeader("Content-Length",parameters.length); 
			req.setRequestHeader('Content-Type','application/x-www-form-urlencoded;charset=UTF-8');
			req.send(parameters);
		}else{
		    alert("请至少使用一种传送方式");
		}
	}else{
		alert("无法创建xmlhttp");
	}
}