How to download Ftp files by date

Hi,

Hi,

my Question is

1) i can download ftp files through my server.
2) but can any one say me how to download ftp files by date

EX: xys03-01-2011.zip
xys03-31-2011.zip

the code which i use is

static void Main(string[] args)
{

string dateString = DateTime.Now.ToString("MM-dd-yyyy");
string filename = string.Format("xys{0}.zip", dateString);
string localPath = "c:\\";
string fileName = filename;
string defaultLocalFolder_MCX = "C:\\";

FastZip fzMCX = new FastZip();

try
{
fzMCX.ExtractZip(defaultLocalFolder_MCX + "\\" + "xys03-31-2011.zip", defaultLocalFolder_MCX, "");
}

catch (Exception)
{
}


FtpWebRequest requestFileDownload = (FtpWebRequest)WebRequest.Create("ftp://localhost/Source/" + fileName);
requestFileDownload.Credentials = new NetworkCredential("test", "test");
requestFileDownload.Method = WebRequestMethods.Ftp.DownloadFile;

FtpWebResponse responseFileDownload = (FtpWebResponse)requestFileDownload.GetResponse();

Stream responseStream = responseFileDownload.GetResponseStream();
FileStream writeStream = new FileStream(localPath + fileName, FileMode.Create);

int Length = 2048;
Byte[] buffer = new Byte[Length];
int bytesRead = responseStream.Read(buffer, 0, Length);
while (bytesRead > 0)
{
writeStream.Write(buffer, 0, bytesRead);
bytesRead = responseStream.Read(buffer, 0, Length);
}
responseStream.Close();
writeStream.Close();

requestFileDownload = null;
responseFileDownload = null;
}

please help me

Thanks in Advance