delphi – 使用Indy组件下载,暂停和恢复下载

这是我目前的代码,这适用于下载文件(没有恢复),但是.现在我想暂停下载关闭我的应用程序,当我的应用程序重新启动后,从最后保存的位置恢复下载.

var
  Http: TIdHTTP;
  MS  : TMemoryStream;
begin
  Result:= True;
  Http  := TIdHTTP.Create(nil);
  MS    := TMemoryStream.Create;
  try

    try
      Http.OnWork:= HttpWork;//this event give me the actual progress of the download process
      Http.Head(Url);
      FSize := Http.Response.ContentLength;
      AddLog('Downloading File '+GetURLFilename(Url)+' - '+FormatFloat('#,',FSize)+' Bytes');
      Http.Get(Url,MS);
      MS.SaveToFile(LocalFile);
    except
      on E : Exception do
      Begin
       Result:=False;
       AddLog(E.Message);
      end;
    end;
  finally
    Http.Free;
    MS.Free;
  end;
end;