FtpWebRequest request;
...
// set target of request
                request = (FtpWebRequest)WebRequest.Create(targetURI);
                // set credential to request
                request.Credentials = credential;
                // set method to execute to request
                request.Method = WebRequestMethods.Ftp.UploadFile;
                // set transfer type
                request.UseBinary = true;
                // if connection isnt closed, dont keep connection after 
                // a command is executed
                request.KeepAlive = false;

                #region Transfer file
                // define size of the to upload file
                request.ContentLength = fileInf.Length;

                int bufferlength = 2048;
                byte[] buff = new byte[bufferlength];
                int contentLen;
                
                // File Stream to read the file to upload
                FileStream fs = fileInf.OpenRead();

                // Stream object to set the request
                Stream strm = request.GetRequestStream();
                
                // Read data in
                contentLen = fs.Read(buff, 0, bufferlength);
                while (contentLen != 0) 
                {
                    // Read data out (To target server)
                    strm.Write(buff, 0, contentLen);
                    contentLen = fs.Read(buff, 0, bufferlength);
                }

                strm.Close();
                fs.Close();
                #endregion