C#贪吃蛇（窗体版本）

string key_name = "start";   //记录键盘状态
Label[] l_b = new Label[30];   //贪吃蛇身体数组
Random r = new Random();    //随机数
int a = 0, b = 0;           //变量，记录坐标
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
//设定初始界面状态
this.Top = 120;
this.Left = 120;
this.Width = 800;
this.Height = 600;
this.BackColor = Color.Black;
//造 蛇 身体，长度为5
for (int i = 0; i < 5; i++)
{
Label lb = new Label();
lb.Width = lb.Height = 20;
lb.Top = 400;
lb.Left = 400 - i * 20;
lb.BackColor = Color.Red;
lb.Text = "O";
lb.Font = new System.Drawing.Font("宋体", 18);
lb.Tag = i;
l_b[i] = lb;
this.Controls.Add(lb);
}
//控件Timer
dt.Tick += new EventHandler(dt_Tick);
//键盘敲击事件
this.KeyDown += new KeyEventHandler(Form1_KeyDown);

snake_food();    //造 蛇 的食物函数
dt.Start();    //Timer 开始
}
void dt_Tick(object sender, EventArgs e)
{
int x_1, y_1;
x_1 = l_b[0].Left;
y_1 = l_b[0].Top;
if (key_name == "start")     //键盘状态处于初始状态
{
l_b[0].Left = x_1 + 20;
snake_move(x_1, y_1);
}
if (key_name == "Right")   //键盘状态处于  向右 状态
{
l_b[0].Left = x_1 + 20;
snake_move(x_1, y_1);
}
if (key_name == "Up")     //键盘状态处于  向上  状态
{
l_b[0].Top = y_1 - 20;
snake_move(x_1, y_1);
}
if (key_name == "Down")   //键盘状态处于  向下  状态
{
l_b[0].Top = y_1 + 20;
snake_move(x_1, y_1);
}
if (key_name == "Left")    //键盘状态处于   向左 状态
{
l_b[0].Left = x_1 - 20;
snake_move(x_1, y_1);
}
//          穿墙设置
if (x_1 > 800)
{
l_b[0].Left = 0; ;
}
if (x_1 < 0)
{
l_b[0].Left = 800;
}
if (y_1 > 600)
{
l_b[0].Top = 0;
}
if (y_1 < 0)
{
l_b[0].Left = 600;
}
//每动一次，判断是否与食物重合
eat_time();
}
//敲击键盘响应
void Form1_KeyDown(object sender, KeyEventArgs e)
{
//记录蛇头坐标
int x_1, y_1;
x_1 = l_b[0].Left;
y_1 =l_b[0].Top;
//获取按了什么键
key_name = e.KeyCode.ToString();

if (e.KeyCode.ToString() == "Right")   //向右
{
l_b[0].Left= x_1 + 20;
snake_move(x_1, y_1);
}
if (e.KeyCode.ToString() == "Up")    //向上
{
l_b[0].Top= y_1 - 20;
snake_move(x_1, y_1);
}
if (e.KeyCode.ToString() == "Down")     //向下
{
l_b[0].Top= y_1 + 20;
snake_move(x_1, y_1);
}
if (e.KeyCode.ToString() == "Left")    //向左
{
l_b[0].Left= x_1 - 20;
snake_move(x_1, y_1);
}
//每按一次，判断是否与食物重合
eat_time();
}
//吃的一瞬间
void eat_time()
{
double x1 = 20, y1 = 20, x2 = 20, y2 = 20;
foreach (Label lb in this.Controls)
{
if (lb.Tag.ToString() == "food".ToString())
{
x2 = lb.Left;
y2 = lb.Top;
}
if (lb.Tag.ToString() == "0".ToString())
{
x1 = lb.Left;  //左
y1 = lb.Top;  //上
}
}
if (x2==x1&&y2==y1)
{
snake_eat();
foreach (Label lb in this.Controls)
{
if (lb.Tag.ToString() == "food".ToString())
{
lb.Top = r.Next(1, 30) * 20;
lb.Left = r.Next(1, 30) * 20;
}
}
}
}
//蛇移动函数
/*主要思路：保证 蛇 的每一块，移动的下次方向为这块（第N块）的前一块（N-1）*/

void snake_move(int x_1, int y_1)
{
int xx = 0;
int yy = 0;
for (int i = 1; l_b[i] != null; i++)
{
if (i >= 3)
{
xx = a;
yy = b;
}
if (i == 1)
{
xx =l_b[i].Left;
yy = l_b[i].Top;
l_b[i].Left= x_1;
l_b[i].Top= y_1;
}
else
{
a =l_b[i].Left;
b = l_b[i].Top;
l_b[i].Left= xx;
l_b[i].Top= yy;
}
}
}
//制造食物
void snake_food()
{
double xx = l_b[0].Left;
double yy = l_b[0].Top;
Label lb = new Label();
lb.Width = 20;
lb.Height = 20;
lb.Top= r.Next(1, 30) * 20;
lb.Left= r.Next(1, 30) * 20;
lb.Tag = "food";
lb.BackColor = Color.Yellow;
this.Controls.Add(lb);
}

//吃过的食物，变为 蛇 的一部分
void snake_eat()
{
int i = 0;
for (; l_b[i] != null; i++)
;
Label lb = new Label();
lb.Width = lb.Height = 20;
lb.Top = b;
lb.Left = a;
lb.BackColor = Color.Red;
lb.Text = "O";
lb.Font = new System.Drawing.Font("宋体", 18);
lb.Tag = i;
l_b[i] = lb;
this.Controls.Add(lb);
}