What's the best way to approach this simple TicTacToe exercise?

Question

Everything is working up to here, I just need to create the method that checks whether someone has won.

Any suggestions on how to tackle this problem effectively?

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace TresEnRaya
{
    public partial class Form1 : Form
    {
        string[,] tablero;
        bool jugador = true;

        public Form1()
        {
            InitializeComponent();
            AsignarTags();
            tablero = new string[3, 3];

            button1.Click += clickHandler;
            button2.Click += clickHandler;
            button3.Click += clickHandler;
            button4.Click += clickHandler;
            button5.Click += clickHandler;
            button6.Click += clickHandler;
            button7.Click += clickHandler;
            button8.Click += clickHandler;
            button9.Click += clickHandler;
        }

        private void AsignarTags()
        {
            button1.Tag = new Posicion() { X = 0, Y = 0 };
            button2.Tag = new Posicion() { X = 0, Y = 1 };
            button3.Tag = new Posicion() { X = 0, Y = 2 };
            button4.Tag = new Posicion() { X = 1, Y = 0 };
            button5.Tag = new Posicion() { X = 1, Y = 1 };
            button6.Tag = new Posicion() { X = 1, Y = 2 };
            button7.Tag = new Posicion() { X = 2, Y = 0 };
            button8.Tag = new Posicion() { X = 2, Y = 1 };
            button9.Tag = new Posicion() { X = 2, Y = 2 };
        }

        private void CambiarSimbolo(Button button)
        {
            Posicion objPosicion = (Posicion)button.Tag;

            if (jugador == true)
            {
                tablero[objPosicion.X, objPosicion.Y] = "X";
                button.Text = "X";
                button.Enabled = false;
                jugador = false;
            }
            else
            {
                tablero[objPosicion.X, objPosicion.Y] = "Y";
                button.Text = "Y";
                button.Enabled = false;
                jugador = true;
            }

            VerificarGanador();
        }

        private void VerificarGanador()
        {
            //THE MAGIC GOES HERE. WINGARDIUM LEVIO-Sah
        }

        private void clickHandler(object sender, EventArgs e)
        {
            Button myButton = (Button)sender;
            switch (myButton.Name)
            {
                case "button1":
                    CambiarSimbolo(myButton);                    
                    break;

                case "button2":
                    CambiarSimbolo(myButton);
                    break;

                case "button3":
                    CambiarSimbolo(myButton);
                    break;

                case "button4":
                    CambiarSimbolo(myButton);
                    break;

                case "button5":
                    CambiarSimbolo(myButton);
                    break;

                case "button6":
                    CambiarSimbolo(myButton);
                    break;

                case "button7":
                    CambiarSimbolo(myButton);
                    break;

                case "button8":
                    CambiarSimbolo(myButton);
                    break;

                case "button9":
                    CambiarSimbolo(myButton);
                    break;
            }
        }        
    }
}

Thanks for the help.

Answer 1

The most effective way is to know the location of the last X or O placed on the board and check only the directions that include this location. This way, you aren't using brute force to determine if a player has won.