ListDirectory.cs

public void ListDirectory(string remoteDirectory, string host, string username, string password)
{
    try
    {
        using (var sftpClient = new SftpClient(host, username, password))
        {
            sftpClient.Connect();

            var files = sftpClient.ListDirectory(remoteDirectory);

            foreach (var file in files)
            {
                Console.WriteLine(file.Name);
            }

            sftpClient.Disconnect();
        }
    }
    catch (Exception e)
    {
        Console.WriteLine(e.Message);
    }
}