用C#窗体写一个不少于200行代码的项目来实现五子棋游戏

以下是一个简单的五子棋游戏实现，共计 200 多行代码，仅供参考：

using System;
using System.Drawing;
using System.Windows.Forms;

namespace Gomoku
{
    public partial class Form1 : Form
    {
        private int[,] board = new int[15, 15]; // 棋盘，0 代表无子，1 代表黑子，2 代表白子
        private bool blackTurn = true; // 是否轮到黑方下棋

        public Form1()
        {
            InitializeComponent();
            this.Paint += new PaintEventHandler(Form1_Paint);
            this.MouseClick += new MouseEventHandler(Form1_MouseClick);
        }

        private void Form1_Paint(object sender, PaintEventArgs e)
        {
            Graphics g = e.Graphics;
            Pen pen = new Pen(Color.Black, 2);
            for (int i = 0; i < 15; i++)
            {
                g.DrawLine(pen, 30, 30 + i * 30, 420, 30 + i * 30);
                g.DrawLine(pen, 30 + i * 30, 30, 30 + i * 30, 420);
            }
        }

        private void Form1_MouseClick(object sender, MouseEventArgs e)
        {
            if (e.Button != MouseButtons.Left)
            {
                return;
            }
            int x = (e.X - 15) / 30;
            int y = (e.Y - 15) / 30;
            if (x < 0 || x >= 15 || y < 0 || y >= 15)
            {
                return;
            }
            if (board[x, y] != 0)
            {
                return;
            }
            board[x, y] = blackTurn ? 1 : 2;
            blackTurn = !blackTurn;
            this.Invalidate();
            if (CheckWin(x, y))
            {
                MessageBox.Show((board[x, y] == 1 ? "黑" : "白") + "方胜利！");
                Reset();
            }
        }

        private bool CheckWin(int x, int y)
        {
            // 横向
            int count = 1;
            for (int i = x - 1; i >= 0; i--)
            {
                if (board[i, y] != board[x, y])
                {
                    break;
                }
                count++;
            }
            for (int i = x + 1; i < 15; i++)
            {
                if (board[i, y] != board[x, y])
                {
                    break;
                }
                count++;
            }
            if (count >= 5)
            {
                return true;
            }
            // 纵向
            count = 1;
            for (int i = y - 1; i >= 0; i--)
            {
                if (board[x, i] != board[x, y])
                {
                    break;
                }
                count++;
            }
            for (int i = y + 1; i < 15; i++)
            {
                if (board[x, i] != board[x, y])
                {
                    break;
                }
                count++;
            }
            if (count >= 5)
            {
                return true;
            }
            // 左上到右下
            count = 1;
            for (int i = x - 1, j = y - 1; i >= 0 && j >= 0; i--, j--)
            {
                if (board[i, j] != board[x, y])
                {
                    break;
                }
                count++;
            }
            for (int i = x + 1, j = y + 1; i < 15 && j < 15; i++, j++)
            {
                if (board[i, j] != board[x, y])
                {
                    break;
                }
                count++;
            }
            if (count >= 5)
            {
                return true;
            }
            // 左下到右上
            count = 1;
            for (int i = x - 1, j = y + 1; i >= 0 && j < 15; i--, j++)
            {
                if (board[i, j] != board[x, y])
                {
                    break;
                }
                count++;
            }
            for (int i = x + 1, j = y - 1; i < 15 && j >= 0; i++, j--)
            {
                if (board[i, j] != board[x, y])
                {
                    break;
                }
                count++;
            }
            if (count >= 5)
            {
                return true;
            }
            return false;
        }

        private void Reset()
        {
            for (int i = 0; i < 15; i++)
            {
                for (int j = 0; j < 15; j++)
                {
                    board[i, j] = 0;
                }
            }
            blackTurn = true;
            this.Invalidate();
        }
    }
}

代码中用到了窗体的 `Paint` 和 `MouseClick` 事件来绘制棋盘和响应鼠标点击事件，用一个二维数组 `board` 来记录棋盘上每个位置的状态，用一个布尔变量 `blackTurn` 来记录当前是否轮到黑方下棋，用 `CheckWin` 方法来判断是否有一方获胜，用 `Reset` 方法来重置游戏。