贪吃蛇方向没法变，按wasd没反应

Question

qi mo编程homework，贪吃蛇不能控制方向，有没有哪位da lao斧正
代码如下：

#include <stdio.h>
#include <graphics.h>
#include<conio.h>
#include<stdlib.h>
#include<mmsystem.h>
#pragma comment (lib,"winmm.lib")

#define SNAKEMAX 500//蛇最长的长度
#define LENGTH 640 //图窗的长宽
#define WIDTH 640

//枚举
enum DIR //表示蛇的方向,用宏定义方向为int型
{
  UP,
  DOWN,
  LEFT,
  RIGHT,
};

 struct Snake
{
    int size;//节数
    int speed;//速度
    int dir;//direct 方向
    POINT coor[SNAKEMAX];//POINT是VS已经定义好的一个结构体

}snake;

 struct FOOD//食物
 {
     int x;
     int y;
     int r;
     bool flag;
     DWORD color;
 }food;

void gameinit()//数据初始化
{
    //播放背景音乐
    mciSendString("open ./rex/贪吃蛇背景音效_bgm.mp3", 0, 0, 0);
    mciSendString("play ./rex/贪吃蛇背景音效_bgm.mp3 repeat", 0, 0, 0);

    srand(GetTickCount());//一般把时间作为种子
     //GetTickCount获取系统开机到现在的毫秒数
    initgraph(LENGTH, WIDTH);//生成图形窗口
    snake.size = 3;
    snake.speed = 6+snake.size/3;
    snake.dir = DOWN;
    
    for (int i = 0; i <snake.size; i++)//设置初始时三个节点坐标
    {
        snake.coor[i].x = 40-10*i;
        snake.coor[i].y = 100;
    }
    //初始化产生随机数，取余数是将范围控制在图形窗口内
    food.x = rand() % LENGTH;
    food.y = rand() % WIDTH;
    food.color = RGB(rand() % 256, rand() % 256, rand() % 256);
    food.r = rand() % 5 + 5;
    food.flag = true;
}

void gamedraw()
{
    BeginBatchDraw();//双缓冲绘图
    setbkcolor(RGB(28, 115, 119));//设置背景颜色
    cleardevice();//
    for (int i = 0; i <= snake.size - 1; i++)
    {
     solidcircle(snake.coor[i].x, snake.coor[i].y, 5);
    }
    if (food.flag)
    {
        solidcircle(food.x, food.y, food.r);
    }
    EndBatchDraw();
}

void snakemove()
{
    for (int i = snake.size-1; i >0 ; i--)
    {
        snake.coor[i] = snake.coor[i - 1];
    }
        switch (snake.dir)
        {
        case RIGHT:
            snake.coor[0].x+=snake.speed;
            if (snake.coor[0].x >= LENGTH - 5)
            {
                snake.coor[0].x = 0;
            }
            break;
        case LEFT:
            snake.coor[0].x-= snake.speed;
            if (snake.coor[0].x <= 5)
            {
                snake.coor[0].x = LENGTH;
            }
            break;
        case UP:
            snake.coor[0].y-= snake.speed;
            if (snake.coor[0].y <= 5)
            {
                snake.coor[0].y = WIDTH;
            }
            break;
        case DOWN:
            snake.coor[0].y+= snake.speed;
            if (snake.coor[0].y >= WIDTH - 5)
            {
                snake.coor[0].y = 0;
            }
            break;
        }
}

void KeyControl()//改变方向
{
    char ch;
    if (_kbhit())//判断是否有按键输入，有的话，输出真
    {
        ch = _getch();
        switch (ch)//_getch读取输入的值
        {
        case 'w':
        case 'W':
        case 72:
        {
            if (snake.dir != DOWN)
            {
                snake.dir = UP;//上下左右键值分别为：72，80，75，77
            }
            break;
        }
        case 's':
        case 'S':
        case 80:
        {
            if (snake.dir != UP)
            {
                snake.dir = DOWN;
            }
            break;
        }
        case 'd':
        case 'D':
        case 77:
        {
            if (snake.dir != LEFT)
            {
                snake.dir = RIGHT;
            }
            break;
        }
        case 'a':
        case 'A':
        case 75:
        {
            if (snake.dir != RIGHT)
            {
                snake.dir = LEFT;
            }
            break;
        }
        case ' '://游戏暂停
        {
            while (1)
            {
                if (_getch() == ' ')
                    return;
            }
            break;
        }
        }
    }
}
void EATFOOD()
{
    if (food.flag && snake.coor[0].x >= food.x - food.r && snake.coor[0].x <= food.x + food.r
        && snake.coor[0].y >= food.y - food.r && snake.coor[0].y <= food.y + food.r)
    {
        food.flag = false;
        snake.size++;
    }
    //食物消失，再次生成一个食物；
    if (food.flag == false)
    {
        food.x = rand() % LENGTH;
        food.y = rand() % WIDTH;
        food.color = RGB(rand() % 255, rand() % 255, rand() % 255);
        food.r = rand() % 5 + 5;
        food.flag = true;
    }
}

int main()
 {
    gameinit();
    
    while (1)
    {
        snakemove();
        gamedraw();
        KeyControl();
        EATFOOD();
        
        Sleep(100);//延迟ms
    }
    return 0;
 }

Answer 1

1：涉及操作系统的库：#pragma comment (lib,"winmm.lib")需要使用管理员权限
2：游戏操作键盘需要使用英文输入法，强制使用英文输入。
3：代码命名规范需要改正
4：win32.api 地址：https://learn.microsoft.com/zh-cn/windows/win32/api/