var req;

function retrieveURL(url) {
	document.getElementById("appendText").innerHTML = "正在载入数据...";    
	if (window.XMLHttpRequest) { // Non-IE browsers    
		req = new XMLHttpRequest();    
		req.onreadystatechange = processStateChange;
		try {
			req.open("POST", url, true); //was get    
		}
		catch (e) { 
			alert(e);
		}
		req.send(null);
	} else {
		if (window.ActiveXObject) { // IE
  
			req = new ActiveXObject("Microsoft.XMLHTTP");
			if (req) {
				req.onreadystatechange = processStateChange;
				req.open("POST", url, true);
				req.send();
			}
		}
	}
}


function processStateChange() {
	if (req.readyState == 4) {
		if (req.status == 200) {
			rt=req.responseText;
			document.getElementById("appendText").innerHTML=rt;	
		} else {
			    document.getElementById("appendText").innerHTML = "";    
		}
	}
}