FTPES with self signed certificate

Here is a small C# code snippet to upload an XML file to an explicit SSL secured FTP server.

When you search nuget for FTP you will get:

But which one do you need? Not all of them support FTPS. Well the checkbox gives it away.

If you search for FTPS you will only get these seven results (at this moment):

So you need the System.Net.FtpClient from https://netftp.codeplex.com/

And here is the C# code to upload an XDocument to an FTPS server:

private void UploadFile(XDocument xDoc, string filename)
{
    using (FtpClient fc = new FtpClient())
    {
        fc.Credentials = new NetworkCredential(username, password);
        fc.Host = hostname;
        fc.EncryptionMode = FtpEncryptionMode.Explicit;
        fc.ValidateCertificate += fc_ValidateCertificate;
        fc.Connect();
        fc.SetWorkingDirectory("/uploaddir");

        using (var ftpStream = fc.OpenWrite(filename, FtpDataType.Binary))
        {
            if (ftpStream != null)
            {
                xDoc.Save(ftpStream);
                ftpStream.Close();
            }
        }
    }
}

static void fc_ValidateCertificate(FtpClient control, FtpSslValidationEventArgs e)
{
    e.Accept = true;
}

Self signed certificates will otherwise always cause an exception in the ftp libraries because the certificates are not really valid. So you manually have to “validate” it.

Good luck!