FTP file size

static NetworkCredential nc = new NetworkCredential("user", "password");

FtpWebRequest request = (FtpWebRequest)FtpWebRequest.CreateDefault(new Uri("ftp://" + ftpServerIP + "/" + sSource));

//(FtpWebRequest)WebRequest.Create(("ftp://ftp.domain.com/doesntexist.txt");
request.Credentials = nc;
request.Method = WebRequestMethods.Ftp.GetFileSize;