using System;

public class Program

{

    public static void Main()

    {

        byte[,] gameValues2D = new byte[3,3] {{0,0,0},{0,0,0},{0,0,0}};

        string number;

        byte currentPiece = 2;

        bool userBlocked = false;

        PrintGameBoard(gameValues2D);

        do

        {

            Console.WriteLine("Please make your selection for '{0}' or enter 'q' to quit..", ConvertToXO(currentPiece));

            number=Console.ReadLine();

            userBlocked = false;

            switch(number)

            {

                case "1":

                    if (gameValues2D[2,0] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[2,0] = currentPiece;

                    break;

                case "2":

                    if (gameValues2D[2,1] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[2,1] = currentPiece;

                    break;

                case "3":

                    if (gameValues2D[2,2] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[2,2] = currentPiece;

                    break;

                case "4":

                    if (gameValues2D[1,0] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[1,0] = currentPiece;

                    break;

                case "5":

                    if (gameValues2D[1,1] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[1,1] = currentPiece;

                    break;

                case "6":

                    if (gameValues2D[1,2] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[1,2] = currentPiece;

                    break;

                case "7":

                    if (gameValues2D[0,0] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[0,0] = currentPiece;

                    break;

                case "8":

                    if (gameValues2D[0,1] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[0,1] = currentPiece;

                    break;

                case "9":

                    if (gameValues2D[0,2] != 0 )

                    {

                        Console.WriteLine(" You cannot place it there. Try it again.");

                        userBlocked = true;

                    }

                    else 

                        gameValues2D[0,2] = currentPiece;

                    break;

                default:

                    break;

            }

            PrintGameBoard(gameValues2D);

            if(!userBlocked)

            {

                if (currentPiece == 1)

                    currentPiece = 2;

                else 

                    currentPiece = 1;

            }

        }

        while( number !="Q" && number !="q"); 

        Console.WriteLine("Thank you for playing!");

    }

     public static void PrintGameBoard(byte[,] values)

     {

         Console.WriteLine("================");    

         Console.WriteLine("| {0,1}  | {1,1}  | {2,1}  |      | 7  | 8  | 9  |",ConvertToXO(values[0,0]), ConvertToXO(values[0,1]), ConvertToXO(values[0,2]));

         Console.WriteLine("|----+----+----|");

         Console.WriteLine("| {0,1}  | {1,1}  | {2,1}  |      | 4  | 5  | 6  |", ConvertToXO(values[1,0]), ConvertToXO(values[1,1]), ConvertToXO(values[1,2]));

         Console.WriteLine("|----+----+----|");

         Console.WriteLine("| {0,1}  | {1,1}  | {2,1}  |      | 1  | 2  | 3  |", ConvertToXO(values[2,0]), ConvertToXO(values[2,1]), ConvertToXO(values[2,2]));

                            //"|TWO

          Console.WriteLine("================");

     }

    public static string ConvertToXO(byte values)

    {

        if (values == 0)        

        {

            return " ";

        }

        else if (values == 1)

        {

            return "X";

        }

        else if (values == 2)

        {

            return "O";

        }

            return " ";

    }

​

}