using System;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("This is the importer class");

        foreach (string line in FTPManager.ReadLine(""))

            Console.WriteLine(line);

    }

}

​

public static class FTPManager

{

    public static IEnumerable<string> ReadLine(string file)

    {

        using (var client = Client.GetClient())

        {

            client.Connect();

            foreach (string line in client.ReadLine())

                yield return line;

            client.Disconnect();

        }

    }

}

​

// Part of the library. 

public class Client : IDisposable

{

    List<string> dummyFileContents = new List<string>()

    {"Line 1", "Line 2"};

    public static Client GetClient()

    {

        return new Client();

    }

​

    public void Connect()

    {

        Console.WriteLine("Connecting");

    }

​

    public void Disconnect()

    {

        Console.WriteLine("Disconnecting");

    }

​

    public IEnumerable<string> ReadLine()

    {

        foreach (var line in dummyFileContents)

            yield return line;

    }

​

    public void Dispose()

    {

        Console.WriteLine("Disposed");

    }

}