Code:
function GetXmlHttpObject()
{
	var xmlHttp=null;
	try
	  {	
	  // Firefox, Opera 8.0+, Safari
	  xmlHttp=new XMLHttpRequest();
	  }
	catch (e)
	  {
	  // Internet Explorer
	  try
	    {
	    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
	    
	    }
	  catch (e)
	    {
	    xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
	    }
	  }
	return xmlHttp;
}
Code:
                xmlHttp = new GetXmlHttpObject();
		
		var url="./scripts/phpAjaxFunction.php";					
		var params = "action=downloadFileToUnix";		
	
		xmlHttp.open("POST", url, true);

		//Send the proper header information along with the request
		xmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
		xmlHttp.setRequestHeader("Content-length", params.length);
		xmlHttp.setRequestHeader("Connection", "close");

		xmlHttp.onreadystatechange = function() {//Call a function when the state changes.
			if(xmlHttp.readyState == 4 && xmlHttp.status == 200) { 
			
				alert(trim(xmlHttp.responseText));
				
			}
		}
		xmlHttp.send(params);
xmlHttp.responseText always return empty, can anyone help?
thanks in advance