關於XMLHTTP的Asynchronouns模式

最近發現Microsoft.XMLHTTP很好用。
想在Delphi中實現一個案頭的用戶端應用，使用MS XML4.0中的XMLHTTP4.0來實現xml的http通訊。
可惜，在Javascript中的非同步模式居然在Delphi中實現不了。。唉，鬱悶啊
MSDN中的說明：
 Note that onreadystatechange is designed for use in scripting environments
  and is not readily accessible in Microsoft Visual Basic or C++.

看一個JavaScript中的執行個體，真是很flexbility

var gThreadRequest=null;
var gRequestXML='<xml>...';

function AsyncDataExchg()
{
    if (gThreadRequest == null)
        AsyncRequest ("http://...", gRequestXML);
}

function AsyncRequest (url, xmlstr)
{
    gThreadRequest = new ActiveXObject("Microsoft.XMLHTTP");
    gThreadRequest.Open("POST", url, true);
    gThreadRequest.onreadystatechange = handleChange;
    gThreadRequest.Send (xmlstr);
}

function handleChange ()
{
    if (gThreadRequest!= null && gThreadRequest.readyState == 4)
        var xmlret = gThreadRequest.responseText;
        // do something...
        gThreadRequest = null;
    }
}