You have to use FtpWebRequest & FtpWebResponse and after that you have to get response.
FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftp://path/test.htm");
request.Method = WebRequestMethods.Ftp.UploadFile;
request.Credentials = new NetworkCredential ("anonymous","abc@xyz.com");
StreamReader sourceStream = new StreamReader("testfile.txt");
byte [] fileContents = Encoding.UTF8.GetBytes(sourceStream.ReadToEnd());
sourceStream.Close();
request.ContentLength = fileContents.Length;
Stream requestStream = request.GetRequestStream();
requestStream.Write(fileContents, 0, fileContents.Length);
requestStream.Close();
FtpWebResponse response = (FtpWebResponse)request.GetResponse();
response.Close();