using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

​

public class Program

{

    public static void Main()

    {

        var Foos = Enumerable.Range(0, 10).Select(x => new Foo

        {

            ID = x+1,

            prop1 = x % 2,

            prop2 = x % 3,

            prop3 = x % 4,

            prop4 = x % 5,

        });

​

​

        Console.WriteLine("### BASIC DEMO ###");

        var order1 = new[] { "prop1", "prop2", "prop3", "prop4" };

        var result1 = DynamicalSort(Foos, order1);

        Console.Write("\n\nOrder1 => ");

        Console.WriteLine( string.Join(", ", result1.Select(o=> o.ID))) ;

​

​

​

        var order2 = new[] { "prop4", "prop1", "prop2", "prop3" };

        var result2 = DynamicalSort(Foos, order2);

        Console.Write("\n\nOrder2 => ");

        Console.WriteLine(string.Join(", ", result2.Select(o => o.ID)));

​

​

        ///////////////////////////////////////////////////////////////////////////////////

        Console.WriteLine("\n\n");

        Console.WriteLine("### Generic DEMO ###");

​

        var order3 = new[] { "prop1", "prop2", };

        var result3 = Foos.OrderByPropertiesNames(order3);

        Console.Write("\n\nOrder3 => ");

        Console.WriteLine(string.Join(", ", result3.Select(o => o.ID)));

​

​

        var order4 = new[] { "prop4", "prop1", };

        var result4 = Foos.OrderByPropertiesNames(order4);

        Console.Write("\n\nOrder4 =>");

        Console.WriteLine(string.Join(", ", result4.Select(o => o.ID)));

    }

​

    public static List<Foo> DynamicalSort(IEnumerable<Foo> source, IEnumerable<string> orderList)

    {

        // First order because m lazy.

        IOrderedEnumerable<Foo> ordered = source.OrderBy(o => o.ID);

        switch (orderList.First())

        {

            case "prop1":

                ordered = source.OrderBy(o => o.prop1);

                break;

            case "prop2":

                ordered = source.OrderBy(o => o.prop2);

                break;

            case "prop3":

                ordered = source.OrderBy(o => o.prop3);

                break;

            case "prop4":

                ordered = source.OrderBy(o => o.prop4);

                break;

        }

​

        foreach (var order in orderList.Skip(1))

            switch (order)

            {

                case "prop1":

                    ordered = ordered.ThenBy(o => o.prop1);

                    break;

                case "prop2":

                    ordered = ordered.ThenBy(o => o.prop2);

                    break;

                case "prop3":

                    ordered = ordered.ThenBy(o => o.prop3);

                    break;

                case "prop4":

                    ordered = ordered.ThenBy(o => o.prop4);

                    break;

            }

        return ordered.ToList();

    }

​

    public class Foo

    {

        public int ID { get; set; }

        public int prop1 { get; set; }

        public int prop2 { get; set; }

        public int prop3 { get; set; }

        public int prop4 { get; set; }

    }

}

public static class Extention

{

    public static IOrderedEnumerable<T> OrderByPropertyName<T>(this IEnumerable<T> source, string propertyName)

    {

        var property = typeof(T).GetProperty(propertyName);

​

        if (property == null) return (IOrderedEnumerable<T>)source; // or throw exception

        else return source.OrderBy(x => property.GetValue(x));

    }

    public static IOrderedEnumerable<T> ThenByPropertyName<T>(this IOrderedEnumerable<T> source, string propertyName)

    {

        var property = typeof(T).GetProperty(propertyName);

​

        if (property == null) return source; // or throw exception

        else return source.ThenBy(x => property.GetValue(x));

    }

​

    public static List<T> OrderByPropertiesNames<T>(this IEnumerable<T> source, IEnumerable<string> propertyName)

    {

        // First order because m lazy.

        var firstOrder = propertyName.First();

        var ordered = source.OrderByPropertyName(firstOrder);

​

        foreach (var order in propertyName.Skip(1))

        {

            ordered = ordered.ThenByPropertyName(order);

        }

        return ordered.ToList();

    }

}