using System;

using System.Globalization;

using System.Collections.Generic;

using System.Data;

using System.Linq;

​

public class Program

{

    public static void Main()

    {

        CultureInfo ci = CultureInfo.GetCultureInfo("hu-HU_technl");

        StringComparer comp = System.StringComparer.Create(ci, false);

​

        DataTable dt = GetData();

        var result = dt

           .Rows

           .OfType<DataRow>()

           .OrderBy(row => (row[1] as string), comp)

           .ThenBy(row => (row[2] as string), comp); 

        foreach (var row in result) {

          Console.WriteLine($"{row[0],3} : {row[1],-20} : {row[2],-20}");

        }

    }

​

    private static DataTable GetData()

    {

        DataTable dt = new DataTable();

        dt.Columns.Add("ID");

        dt.Columns.Add("Name");

        dt.Columns.Add("LastName");

        dt.Rows.Add("1", "Agoston", "Sworder");

        dt.Rows.Add("2", "Ágoston", "Aubert");

        dt.Rows.Add("3", "Țală", "Proctor");

        dt.Rows.Add("4", "Alszegi", "Grewer");

        dt.Rows.Add("5", "Antal", "Meader");

        dt.Rows.Add("6", "Anton", "Grindall");

        dt.Rows.Add("7", "Archișan", "Banthorpe");

        dt.Rows.Add("8", "Arghișan", "Hanigan");

        dt.Rows.Add("9", "Arteme", "Fuzzard");

        dt.Rows.Add("10", "Bács", "Altree");

        dt.Rows.Add("11", "Baga", "Cosans");

        dt.Rows.Add("12", "Bakó", "Harmon");

        dt.Rows.Add("13", "Bălănoiu", "Coughlin");

        dt.Rows.Add("14", "Balázs", "Yakunchikov");

        dt.Rows.Add("15", "Balázs K", "Sherrock");

        dt.Rows.Add("17", "Bardocz", "X");

        dt.Rows.Add("16", "Balló", "Roo");

        dt.Rows.Add("17", "Bardocz", "Abba");

        dt.Rows.Add("18", "Baricz", "Marran");

        dt.Rows.Add("19", "Bartalis", "Gile");

        dt.Rows.Add("20", "Bartha", "Miroy");

        dt.Rows.Add("21", "Bátori", "Kerin");

        dt.Rows.Add("22", "Bazsó", "Tolle");

        return dt;

    }

}