小菜學習Winform（一）貪吃蛇2

前言

　　上一篇《小菜學習Winform（一）貪吃蛇》中實現了簡單版的貪吃蛇，在文章末也提到需要優化的地方，比如使用oo、得分模式、速度加快模式和減少界面重繪。因為是優化篇，實現方式上一篇有，這一篇大家看看代碼就行。當然小菜不是搞游戲開發的，程序可能有很多問題，這里點到即止，有時間小菜會加強學習。

實現

　　說到oo可能一說一大堆，這里面小菜只是簡單的把貪吃蛇抽象出來，先來說蛇，具有的屬性和行為，屬性比如蛇的長度、蛇的寬度、蛇的行動方向等；行為比如是否吃到食物、是否撞牆等，那我們可以抽象一個蛇的類，這樣實現：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;

namespace SnakeGame
{
    public class Snake
    {
        public int SnkWidth = 16;//蛇的每個點的寬度
        public const int SnakeMaxLength = 500;//最大長度
        public Point[] SnkLct = new Point[SnakeMaxLength];
        public int SnkLen;//蛇的長度
        public byte SnkDrt = 2;//方向 1上 2右 3下 4左
        
        /// <summary>
        /// 屬性初始化
        /// </summary>
        public void SnakeInit()
        {
            int start = 0;
            this.SnkLen = 5;
            for (int i = 5; i >=1; i--)
            {
                this.SnkLct[i].X = start;
                this.SnkLct[i].Y = 32;
                start += this.SnkWidth;
            }
            this.SnkDrt = 2;//初始方向
        }
        /// <summary>
        /// 判斷是否撞到自己
        /// </summary>
        /// <returns></returns>
        public bool CheckSnakeHeadInSnakeBody()
        {
            return this.CheckInSnakeBody(this.SnkLct[1].X, this.SnkLct[1].Y, 2);
        }
        /// <summary>
        /// 檢查輸入的坐標是否在蛇的身上
        /// </summary>
        /// <param name="x"></param>
        /// <param name="y"></param>
        /// <param name="snkHead"></param>
        /// <returns></returns>
        public bool CheckInSnakeBody(int x, int y, int snkHead)
        {
            for (int i =snkHead; i <=this.SnkLen; i++)
            {
                if(x==this.SnkLct[i].X&&y==this.SnkLct[i].Y)
                {
                    return true;
                }
            }
            return false;
        }
        /// <summary>
        /// 判斷是否撞牆
        /// </summary>
        /// <returns></returns>
        public bool CheckSnakeBodyInFrm()
        {
            if (this.SnkLct[1].X >= 560 || this.SnkLct[1].Y >= 512 || this.SnkLct[1].X < 0 || this.SnkLct[1].Y < 32)
                  return true;
            else
                 return false;
        }
        /// <summary>
        /// 判斷是否吃到食物
        /// </summary>
        /// <param name="FoodLct"></param>
        /// <returns></returns>
        public bool EatedFoot(Point FoodLct)
        {
            if (SnkLct[1].X == FoodLct.X && SnkLct[1].Y == FoodLct.Y)
            {
                if (SnkLen < SnakeMaxLength)
                {
                    SnkLen++;
                    SnkLct[SnkLen].X = SnkLct[SnkLen - 1].X;
                    SnkLct[SnkLen].Y = SnkLct[SnkLen - 1].Y;
                }
                return true;         
            }
            else
                return false;         
        }
        /// <summary>
        /// 設置Point數組坐標
        /// </summary>
        /// <param name="drc"></param>
        public void Forward(int drc)
        {
            Point tmp = new Point();
            tmp.X = SnkLct[1].X;
            tmp.Y = SnkLct[1].Y;
            for (int i = SnkLen; i > 1; i--)
            {//蛇頭動，把蛇頭的坐標逐個后移(蛇身往蛇頭方向位移) 
                SnkLct[i].X = SnkLct[i - 1].X;
                SnkLct[i].Y = SnkLct[i - 1].Y;
            }

            switch (drc)
            {//根據設置的方向，計算蛇頭的坐標 
                case 1:
                    SnkLct[1].X = tmp.X;
                    SnkLct[1].Y = tmp.Y - SnkWidth;
                    break; //上 
                case 2:
                    SnkLct[1].X = tmp.X + SnkWidth;
                    SnkLct[1].Y = tmp.Y;
                    break; //右 
                case 3:
                    SnkLct[1].X = tmp.X;
                    SnkLct[1].Y = tmp.Y + SnkWidth;
                    break; //下 
                case 4:
                    SnkLct[1].X = tmp.X - SnkWidth;
                    SnkLct[1].Y = tmp.Y;
                    break; //左 
            }
        }
    }
}

　　抽象完蛇，那我們再說下貪吃蛇游戲，貪吃蛇這個游戲具有的元素有：蛇、食物、得分等，那我們這樣來表現：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Drawing;

namespace SnakeGame
{
    public class Game
    {
        public Point FoodLct = new Point();//緩存食物的坐標
        public int score = 0;//得分
        public bool pause;//暫停
        public Snake snake = new Snake();
        /// <summary>
        /// 游戲初始化
        /// </summary>
        public void GameInit()
        {
            this.pause = false;
            this.score = 0;
            this.snake.SnakeInit();//初始化
        }
        /// <summary>
        /// 隨機顯示食物
        /// </summary>
        public void ShowFood()
        {
            Random rmd = new Random();
            int x, y;
            x = rmd.Next(0, 35) * this.snake.SnkWidth;
            y = 32 + rmd.Next(0, 30) * this.snake.SnkWidth;
            while (this.snake.CheckInSnakeBody(x,y,1))
            {
                x = rmd.Next(0,32)*this.snake.SnkWidth;
                y = 32 + rmd.Next(0, 30) * this.snake.SnkWidth;
            }
            FoodLct.X = x;
            FoodLct.Y = y;
        }
        /// <summary>
        /// 分數
        /// </summary>
        /// <returns></returns>
        public bool AddScore()
        {
            if(this.snake.EatedFoot(FoodLct))
            {
                this.score += 10;
            return true;
            }
            return false;
        }
        /// <summary>
        /// 判斷游戲是否結束
        /// </summary>
        /// <returns></returns>
        public bool Dead()
        {
            return this.snake.CheckSnakeBodyInFrm()||this.snake.CheckSnakeHeadInSnakeBody();
        }
    }
}

　　其實使用oo還有很多地方需要細化，這里不是講oo，所以只是簡單的帶過下。

　　然后是得分模式，就是蛇吃到一個食物就加10分，這個在AddScore()方法中有實現：

        /// <summary>
        /// 分數
        /// </summary>
        /// <returns></returns>
        public bool AddScore()
        {
            if(this.snake.EatedFoot(FoodLct))
            {
                this.score += 10;
                return true;
            }
            return false;
        }

　　再者是加速模式，蛇吃到一定量的時候后，難度會增加，爬行的速度會更快，這個可以在timer事件里面根據得分設置timer的執行間隔時間：

            if (this.game.score < 100)
            {
                this.timMove.Interval = 150;
            }
            else if (this.game.score < 150)
            {
                this.timMove.Interval = 100;
            }
            else
            {
                this.timMove.Interval = 50;
            }

　　最后是減少界面重繪這個問題，因為小菜不是搞游戲開發的，那我只能減少界面的重繪數量，這邊我是這樣實現的，食物用label控件，顯示用定位來體現，蛇的動作還是用GDI+來繪制。

　　主程序代碼：

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 SnakeGame
{
    public partial class MainFrom : Form
    {
        public MainFrom()
        {
            InitializeComponent();
        }
        public Game game = new Game();
        /// <summary>
        /// 繪制一個方塊
        /// </summary>
        /// <param name="x"></param>
        /// <param name="y"></param>
        private void DrawShape(int x, int y)
        {
            Graphics g = this.CreateGraphics();
            Pen pen = new Pen(Color.Green, 1);
            SolidBrush brush = new SolidBrush(Color.GreenYellow);
            g.DrawRectangle(pen, x, y, 15, 15);
            g.FillRectangle(brush, x, y, 15, 15);
        }
        /// <summary>
        /// 開始
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void tsmiGameStart_Click(object sender, EventArgs e)
        {
            this.tsmiGamePause.Enabled = true;
            this.game.GameInit();
            this.timMove.Start();
            this.game.ShowFood();
            this.lblFood.Location = this.game.FoodLct;
        }
        /// <summary>
        /// 暫停
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void tsmiGamePause_Click(object sender, EventArgs e)
        {
            if (this.game.pause == false)
            {
                this.game.pause = true;
                this.timMove.Enabled = false;
            }
            else
            {
                this.game.pause = false;
                this.timMove.Enabled = true;
            }
            this.tsmiGamePause.Checked = this.game.pause;
        }
        /// <summary>
        /// 退出
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void tsmiGameExit_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }
        /// <summary>
        /// 加載
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void MainFrom_Load(object sender, EventArgs e)
        {
            this.timMove.Interval = 150;
            this.tsmiGamePause.Enabled = false;
        }
        /// <summary>
        /// 時間事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void timMove_Tick(object sender, EventArgs e)
        {
            if (this.game.score < 100)
            {
                this.timMove.Interval = 150;
            }
            else if (this.game.score < 150)
            {
                this.timMove.Interval = 100;
            }
            else
            {
                this.timMove.Interval = 50;
            }
            Graphics g = this.CreateGraphics();
            g.Clear(Color.DarkKhaki);//清除整個畫面
            this.game.snake.Forward(this.game.snake.SnkDrt);
            for (int i = 1; i <= this.game.snake.SnkLen; i++)
            {
                DrawShape(this.game.snake.SnkLct[i].X, this.game.snake.SnkLct[i].Y);
            }
            if (this.game.AddScore())
            {
                this.game.ShowFood();
                this.lblFood.Location = this.game.FoodLct;
            }
            this.Text = this.Text.Substring(0, this.Text.IndexOf(" ： ") + 9) + this.game.score.ToString();
            if (this.game.Dead())
            {
                this.timMove.Enabled = false;
                this.tsmiGamePause.Enabled = false;
                MessageBox.Show("游戲結束!\n" + "得分:" + this.game.score, "", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
        }
        /// <summary>
        /// 方向鍵
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void MainFrom_KeyDown(object sender, KeyEventArgs e)
        {
            if (this.game.pause == false)
            {
                string key = e.KeyCode.ToString();
                switch (key)
                {
                    // 按 上方向鍵 或 小鍵盤的8鍵時，向上移動一單元格
                    case "Up":
                        {
                            // 正在向下走時，不允許向上；下面相同
                            if (this.game.snake.SnkDrt != 3)
                                this.game.snake.SnkDrt = 1;
                            break;
                        }
                    case "Right":
                        {
                            if (this.game.snake.SnkDrt != 4)
                                this.game.snake.SnkDrt = 2;
                            break;
                        }
                    case "Down":
                        if (this.game.snake.SnkDrt != 1)
                            this.game.snake.SnkDrt = 3;
                        break;

                    case "Left":
                        if (this.game.snake.SnkDrt != 2)
                            this.game.snake.SnkDrt = 4;
                        break;
                }
            }
        }
    }
}

　　運行截圖：

　　程序下載：貪吃蛇2

　　附錄：小菜學習編程-Winform系列（初學者）

后記

　　這個小程序做到這，可能還有很多的問題，有時間小菜會盡量完善下。當然這個小游戲只是起到引子的作用，下面小菜會整理些winfrom其他相關的，希望大家可以關注下。