How to Download Numerous Files from FTP using C#?

问题

I need to run a console application at scheduled intervals that needs to download only .pgp files from an FTP site. Any pgp file in the FTP must be downloaded. I've found the sample code to get a directory listing of the FTP and have written that here:

FtpWebRequest req = (FtpWebRequest)WebRequest.Create("ftp://ourftpserver");
        req.Method = WebRequestMethods.Ftp.ListDirectoryDetails;

        req.Credentials = new NetworkCredential("user", "pass");

        FtpWebResponse response = (FtpWebResponse)req.GetResponse();

        Stream responseStream = response.GetResponseStream();
        StreamReader reader = new StreamReader(responseStream);
        Console.WriteLine(reader.ReadToEnd());

        Console.WriteLine("Directory List Complete, status {0}", response.StatusDescription);

        reader.Close();
        response.Close();

What must I do to download all files of the type .pgp from the directory listing and save them in a local directory on our server?

回答1:

The FtpWebRequest and FtpWebResponse objects are really designed do make single requests (i.e. download single files, etc.)

You're looking for an FTP client. There isn't one in the .NET Framework, but there's a free one, System.Net.FtpClient that apparently works quite well.

回答2:

There is very good library which you can use https://sshnet.codeplex.com/ Code snippet: You need to pass folder path where you want to download files as localFilesPath and Ftp folder path from where you want to download as remoteFTPPath.

public static void DownloadFilesFromFTP(string localFilesPath, string remoteFTPPath)
        {
            using (var sftp = new SftpClient(Settings.Default.FTPHost, Settings.Default.FTPUsername, Settings.Default.FTPPassword))
            {
                sftp.Connect();
                sftp.ChangeDirectory(remoteFTPPath);
                var ftpFiles = sftp.ListDirectory(remoteFTPPath, null);
                StringBuilder filePath = new StringBuilder();
                foreach (var fileName in ftpFiles)
                {

                    filePath.Append(localFilesPath).Append(fileName.Name);
                    string e = Path.GetExtension(filePath.ToString());
                    if (e == ".csv")
                    {
                        using (var file = File.OpenWrite(filePath.ToString()))
                        {
                            sftp.DownloadFile(fileName.FullName, file, null);
                            sftp.Delete(fileName.FullName);
                        }
                    }
                    filePath.Clear();
                }
                sftp.Disconnect();
            }
        }

回答3:

code for download file from ftp.

        FtpWebRequest request = (FtpWebRequest)WebRequest.Create("ftp://127.0.0.0/my.txt");
        request.Method = WebRequestMethods.Ftp.DownloadFile;
        request.Credentials = new NetworkCredential("userid", "pasword");
        FtpWebResponse response = (FtpWebResponse)request.GetResponse();
        Stream responseStream = response.GetResponseStream();
        FileStream file = File.Create(@c:\temp\my.txt);
        byte[] buffer = new byte[32 * 1024];
        int read;
        //reader.Read(

        while ((read = responseStream.Read(buffer, 0, buffer.Length)) > 0)
        {
            file.Write(buffer, 0, read);
        }

        file.Close();
        responseStream.Close();
        response.Close();

回答4:

Ultimate FTP can help you. The following code snippet demonstrates that:

using ComponentPro.IO;
using ComponentPro.Net;

...

// Create a new instance.
Ftp client = new Ftp();

// Connect to the FTP server.
client.Connect("myserver");

// Authenticate.
client.Authenticate("userName", "password");

// ...

// Get all directories, subdirectories, and files from remote folder '/myfolder' to 'c:\myfolder'.
client.DownloadFiles("/myfolder", "c:\\myfolder");

// Get all directories, subdirectories, and files that match the specified search pattern from remote folder '/myfolder2' to 'c:\myfolder2'.
client.DownloadFiles("/myfolder2", "c:\\myfolder2", "*.pgp");

// or you can simply put wildcard masks in the source path, our component will automatically parse it.
// download all *.pgp files from remote folder '/myfolder2' to local folder 'c:\myfolder2'.
client.DownloadFiles("/myfolder2/*.pgp", "c:\\myfolder2");

// Download *.pgp files from remote folder '/myfolder2' to local folder 'c:\myfolder2'.
client.DownloadFiles("/myfolder2/*.pgp", "c:\\myfolder2");

// Get files in the folder '/myfolder2' only.
TransferOptions opt = new TransferOptions(true, RecursionMode.None, false, (SearchCondition)null, FileExistsResolveAction.Overwrite, SymlinksResolveAction.Skip);
client.DownloadFiles("/myfolder2", "c:\\myfolder2", opt);

// ...

// Disconnect.
client.Disconnect();

http://www.componentpro.com/doc/ftp has more examples.

来源：https://stackoverflow.com/questions/18111877/how-to-download-numerous-files-from-ftp-using-c

标签

ftpwebrequest