class Program
{
    static void Main(string[] args)
    {
        CsvRowReader.Use();

        var text = "First,LastnJohn,Doen";
        var file = NameFile.Parse(text);
        foreach (var n in file)
            WriteLine($"{n.First} {n.Last}");
    }
}

public class NameFile : RowFile<NameFile, FullName>
{
    protected override IEnumerable<FullName> Read(RowReader reader)
    {
        while (reader.Read())
            yield return new FullName
            {
                First = reader.Get<string>("First"),
                Last = reader.Get<string>("Last")
            };
    }
}

public class FullName
{
    public string First { get; set; }
    public string Last { get; set; }
}

public abstract class RowFile<TFile, TRow> : Enumerable<TRow>
    where TFile : RowFile<TFile, TRow>, new()
{
    public static readonly TFile Empty = new TFile();

    public static TFile Parse(string text) =>
        Load(new StringReader(text));

    public static TFile Load(string filePath) =>
        Load(File.OpenText(filePath));

    public static TFile Load(Stream stream) =>
        Load(new StreamReader(stream));

    public static TFile Load(TextReader reader)
    {
        var file = new TFile();
        file.Rows = file.Read(RowReader.Create(reader));
        return file;
    }

    public sealed override IEnumerator<TRow> GetEnumerator() =>
        Rows.GetEnumerator();

    protected abstract IEnumerable<TRow> Read(RowReader read);
    IEnumerable<TRow> Rows { get; set; } = new TRow[0];
}

public abstract class RowReader : IDisposable
{
    public static Func<TextReader, RowReader> Create { get; protected set; }
    public abstract void Dispose();
    public abstract bool Read();
    public abstract T Get<T>(string name);
}

public abstract class Enumerable<T> : IEnumerable<T>
{
    public abstract IEnumerator<T> GetEnumerator();
    IEnumerator IEnumerable.GetEnumerator() =>
        GetEnumerator();
}

public class CsvRowReader : RowReader
{
    public static void Use() =>
        Create = reader => new CsvRowReader(reader);

    CsvRowReader(TextReader reader)
    {
        Reader = new CsvReader(reader);
        Reader.Read();
        Reader.ReadHeader();
    }

    CsvReader Reader { get; }

    public override void Dispose() =>
        Reader.Dispose();

    public override bool Read() =>
        Reader.Read();

    public override T Get<T>(string name) =>
        Reader.GetField<T>(name);
}