C# 实现FTP上传与下载

向FTP服务器下载文件的简单实例

string filePath = "d:\\";
            string fileName = "lhking.txt"; //文件下载之后要保存的路径和文件名
            FtpWebRequest reqFTP;
            try
            {
                FileStream outputStream = new FileStream(filePath +"\\" + fileName, FileMode.Create);
                string filename = "ip.txt";
                string ftpServerIP = "222.76.217.24";
                reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri("ftp://" +ftpServerIP + "/" + filename));
                reqFTP.Method = WebRequestMethods.Ftp.DownloadFile;
                reqFTP.UseBinary = true;
                reqFTP.Credentials = new NetworkCredential("l","l");

                FtpWebResponse response = (FtpWebResponse)reqFTP.GetResponse();
                Stream ftpStream = response.GetResponseStream();
                long cl = response.ContentLength;
                int bufferSize = 2048;
                int readCount;
                byte[] buffer = new byte[bufferSize];

                readCount = ftpStream.Read(buffer, 0, bufferSize);
                while (readCount > 0)
                {
                    outputStream.Write(buffer, 0, readCount);
                    readCount = ftpStream.Read(buffer, 0, bufferSize);
                }
                ftpStream.Close();
                outputStream.Close();
                response.Close();
            }
            catch (Exception err) 
            { 
                MessageBox.Show(err.Message,"Download Error");
            }

向FTP服务器上传文件的简单实例

string filename = "ip.txt";
            string ftpServerIP = "222.76.217.24";
            FileInfo fileInf = new FileInfo(filename);
            string uri = "ftp://" + ftpServerIP + "/" + fileInf.Name;
            FtpWebRequest reqFTP;
            reqFTP = (FtpWebRequest)FtpWebRequest.Create(new Uri("ftp://" + ftpServerIP + "/" + fileInf.Name));
            reqFTP.Credentials = new NetworkCredential("l","l");
            reqFTP.KeepAlive = false;
            reqFTP.Method = WebRequestMethods.Ftp.UploadFile;
            reqFTP.UseBinary = true;
            reqFTP.ContentLength = fileInf.Length;

            int buffLength = 2048;
            byte[] buff = new byte[buffLength];
            int contentLen;
            FileStream fs = fileInf.OpenRead();
            try
            {
                Stream strm = reqFTP.GetRequestStream();
                contentLen = fs.Read(buff, 0, buffLength);
                while (contentLen != 0)
                {
                    strm.Write(buff, 0, contentLen);
                    contentLen = fs.Read(buff, 0, buffLength);
                }
                strm.Close();
                fs.Close();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message, "Upload Error");
            }

如果想把Stream转换为字符串的话，下面这样写就行了。
                StreamReader sr = new StreamReader(ftpStream, Encoding.Default);
                string str = sr.ReadToEnd();