using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        //your collection  - change the order, it shouldn't matter

        List<Thing> thingList = new List<Thing>

        {

            new Thing { X ="A", Y = "B", Z="C" },

            new Thing { X ="X", Y = "Y", Z="Z" },

            new Thing { X ="1", Y = "2", Z="3" },

            new Thing { X ="!", Y = "@", Z="#" },

        };

​

        Console.WriteLine("thing list order - unsorted");

        Console.WriteLine();

        thingList.ForEach(thing => Console.WriteLine(thing));

​

        //try match on 3rd condition X == "!"

        var q = thingList

            .OrderByDescending(t => t.Z == ".") //1st condition

            .ThenByDescending(t => t.Y == "Z") //2nd condition

            .ThenByDescending(t => t.X == "!"); //3rd ...

        Console.WriteLine();

        Console.WriteLine("try match on 3rd condition X == \"!\"");

        Console.WriteLine(q.FirstOrDefault());

​

        //try match on 2nd condition Y == "Y"

        q = thingList

            .OrderByDescending(t => t.Z == ".") //1st condition

            .ThenByDescending(t => t.Y == "Y") //2nd condition

            .ThenByDescending(t => t.X == "!"); //3rd ... also a match but lower score

​

        Console.WriteLine();

        Console.WriteLine("try match on 3rd condition Y == \"Y\"");

        Console.WriteLine(q.FirstOrDefault());

​

        Console.WriteLine();

        Console.WriteLine("Changing list order...");

​

        //change order of items in list

        thingList = new List<Thing>

        {

            new Thing { X ="1", Y = "2", Z="3" },

            new Thing { X ="A", Y = "B", Z="C" },

            new Thing { X ="!", Y = "@", Z="#" },

            new Thing { X ="X", Y = "Y", Z="Z" },

        };

​

        Console.WriteLine("thing list order - changed - it now looks like this");

        Console.WriteLine();

        thingList.ForEach(thing => Console.WriteLine(thing));

        Console.WriteLine();

        //try again

​

        //try match on 3rd condition X == "!"

        q = thingList

            .OrderByDescending(t => t.Z == ".") //1st condition

            .ThenByDescending(t => t.Y == "Z") //2nd condition

            .ThenByDescending(t => t.X == "!"); //3rd ...

​

        Console.WriteLine("try match on 3rd condition X == \"!\"");

        Console.WriteLine(q.FirstOrDefault());

        Console.WriteLine();

        //try match on second condition Y == "Y"

        q = thingList

            .OrderByDescending(t => t.Z == ".") //1st condition

            .ThenByDescending(t => t.Y == "Y") //2nd condition

            .ThenByDescending(t => t.X == "!"); //3rd ... also a match but lower score

​

        Console.WriteLine("try match on 3rd condition Y == \"Y\"");

        Console.WriteLine(q.FirstOrDefault());

    }

    class Thing

    {

        public string X { get; set; }

        public string Y { get; set; }

        public string Z { get; set; }

​

        public override string ToString()

        {

            //this doesnt work on dotnetfiddle -> return $"X: {X} Y: {Y} Z: {Z}"; // so its re-written to string.Format below

            return string.Format("X: {0} Y: {1} Z: {2}", X, Y, Z);

        }

    }

​

}