C#五子棋实现详解

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


namespace 五子棋
{
    public partial class Form1 : Form
    {
        int index = 0;

        private int[,] virtualGobangBoard = new int[15, 15];//虚拟棋盘
        private PictureBox[,] gobangPictureBox = new PictureBox[15, 15];//棋子
        private Point lastMovePoint = new Point(-1, -1);
        private bool blnBegin;
        private const int black = -1, white = 1, background = 0;
        private int personGobangColor, computerGobangColor;
        private int totalGobangCount = 0;
        private Stack backStack = new Stack();//用于悔棋的栈
        private Stack backTrackStack = new Stack();//用于回溯的栈 
        const int M = 1;//预测的步数

        public Form1()
        {
            InitializeComponent();
            gobangBoardGroupBox.Paint += new PaintEventHandler(gobangBoardGroupBox_Paint);
            InitializeGobangBoard();
            gobangBoardGroupBox.MouseMove += new MouseEventHandler(gobangBoardGroupBox_MouseMove);
            this.MouseMove += new MouseEventHandler(Form1_MouseMove);
            gobangBoardGroupBox.MouseClick += new MouseEventHandler(gobangBoardGroupBox_MouseClick);
            this.Text = "五子棋";
            
        }

        private void InitializeGobangBoard()//初始化棋盘
        {
            gobangBoardGroupBox.Paint += new PaintEventHandler(gobangBoardGroupBox_Paint);
            int x, y;
            for (x = 0; x < 15; x++)
                for (y = 0; y < 15; y++)
                {
                    gobangPictureBox[x, y] = new PictureBox();
                    gobangPictureBox[x, y].Location = new Point(10 + x * 40, 10 + y * 40);
                    gobangPictureBox[x, y].Size = new Size(40, 40);
                    gobangPictureBox[x, y].BackColor = Color.Transparent;
                    gobangPictureBox[x, y].SizeMode = PictureBoxSizeMode.CenterImage;
                    gobangPictureBox[x, y].Visible = false;
                    gobangBoardGroupBox.Controls.Add(gobangPictureBox[x, y]);
                }
        }

        private void gobangBoardGroupBox_Paint(object sender, PaintEventArgs e)