如何把webbrowser_beforeNavigate()中的参数postdata转变为能够识别的数据格式?

Question

void __fastcall TfrmMain::cwbIeBeforeNavigate2(TObject *Sender,
      LPDISPATCH pDisp, TVariant *URL, TVariant *Flags,
      TVariant *TargetFrameName, TVariant *PostData, TVariant *Headers,
      TOLEBOOL *Cancel)
{
 Variant* vPostData;
 String sTemp;
        vPostData = (Variant*)PostData->byref;
        urlDecoder->InputString =  (char*)vPostData->ArrayLock();
        sTemp = urlDecoder->Decode;
        vPostData->ArrayUnlock();
}