效果图：
完整代码如下：
html：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <link rel="stylesheet" href="index.css" > <script src="index.js"></script> </head> <body> <div class="content"> <div class="btn startBtn"><button></button></div> <div class="btn pauseBtn"><button></button></div> <div id="snakeWrap"> <!-- <div class="snakeHead"></div> <div class="snakeBody"></div> <div class="food"></div> --> </div> </div> </body> </html>
css：
.content {
position: relative;
width: 640px;
height: 640px;
margin: 100px auto;
}
.btn {
width: 100%;
height: 100%;
position: absolute;
top: 0;
left: 0;
background-color: black;
opacity: .1;
z-index: 2;
}
.btn button {
background: none;
border: none;
background-size: 100% 100%;
cursor: pointer;
outline: none;
position: absolute;
left: 50%;
top: 50%;
}
.startBtn button {
width: 200px;
height: 80px;
background-image: url(../贪吃蛇/img/btn.gif);
margin-left: -100px;
margin-top: -40px;
}
.pauseBtn {
display: none;
}
.pauseBtn button {
width: 70px;
height: 70px;
background-image: url(../贪吃蛇/img/btn4.png);
margin-left: -35px;
margin-top: -35px;
}
#snakeWrap {
width: 600px;
height: 600px;
background-color: pink;
border: 20px solid purple;
position: relative;
}
/* #snakeWrap div {
width: 20px;
height: 20px;
} */
.snakeHead {
background-image: url(../贪吃蛇/img/snake.png);
background-size: cover;
}
.snakeBody {
background-color: rgb(85, 146, 126);
border-radius: 50%;
}
.food {
background-image: url(../贪吃蛇/img/草莓.png);
background-size: cover;
}js：
window.addEventListener('load', function() {
// 声明方块的宽高，行数和列数
var sw = 20,
sh = 20,
tr = 30,
td = 30;
var snake = null, //蛇的实例
food = null, //食物的实例
game = null; //游戏的实例
function Square(x, y, classname) {
this.x = sw * x;
this.y = sh * y;
this.class = classname;
this.viewContent = document.createElement('div'); //方块对应的DOM元素
this.viewContent.className = this.class;
this.parent = document.getElementById('snakeWrap'); //方块的父级
}
//创建方块DOM，并添加到页面里
Square.prototype.create = function() {
this.viewContent.style.position = 'absolute';
this.viewContent.style.width = sw + 'px';
this.viewContent.style.height = sh + 'px';
this.viewContent.style.left = this.x + 'px';
this.viewContent.style.top = this.y + 'px';
this.parent.appendChild(this.viewContent);
};
Square.prototype.remove = function() {
this.parent.removeChild(this.viewContent);
};
//蛇
function Snake() {
this.head = null //存蛇头的信息
this.tail = null //存蛇尾的信息
this.pos = []; //存蛇身上每个方块的位置
//存储蛇走的方向，用一个对象来表示
this.directionNum = {
left: {
x: -1,
y: 0,
rotate: 180
},
right: {
x: 1,
y: 0,
rotate: 0
},
up: {
x: 0,
y: -1,
rotate: -90
},
down: {
x: 0,
y: 1,
rotate: 90
}
};
}
//初始化
Snake.prototype.init = function() {
//创建蛇头
var snakeHead = new Square(2, 0, 'snakeHead');
snakeHead.create();
this.head = snakeHead; //存储蛇头信息
this.pos.push([2, 0]); //把蛇头的位置存起来
//创建蛇身体1
var snakeBody1 = new Square(1, 0, 'snakeBody');
snakeBody1.create();
this.pos.push([1, 0]); //把蛇身1的坐标存起来
//创建蛇身体2
var snakeBody2 = new Square(0, 0, 'snakeBody');
snakeBody2.create();
this.tail = snakeBody2; //把蛇尾的信息存起来
this.pos.push([0, 0]); //把蛇身1的坐标存起来
//形成链表关系
snakeHead.last = null;
snakeHead.next = snakeBody1;
snakeBody1.last = snakeHead;
snakeBody1.next = snakeBody2;
snakeBody2.last = snakeBody1;
snakeBody2.next = null;
//给蛇添加一条属性，用来表示蛇的走向
this.direction = this.directionNum.right; //默认让蛇往右走
};
//该方法用来获取蛇头的下一个位置对应的元素，要根据元素做不同的事情
Snake.prototype.getNextPos = function() {
var nextPos = [ //蛇头要走的下一个点的坐标
this.head.x / sw + this.direction.x,
this.head.y / sh + this.direction.y
];
// console.log(nextPos[0]);
//下个点是自己，游戏结束
var selfCollied = false; //是否撞到自己，默认是否
//value表示数组中的某一项
this.pos.forEach(function(value) {
// console.log(nextPos[0], value[0]);
if (value[0] == nextPos[0] && value[1] == nextPos[1]) {
selfCollied = true;
// console.log(2);
}
});
if (selfCollied) {
console.log('撞到自己了!');
this.strategies.die.call(this);
return;
}
// 下个点是墙，游戏结束
if (nextPos[0] < 0 || nextPos[1] < 0 || nextPos[0] > td - 1 || nextPos[1] > tr - 1) {
console.log('撞墙!');
this.strategies.die.call(this);
return;
}
// 下个点是食物，吃
if (food && food.pos[0] == nextPos[0] && food.pos[1] == nextPos[1]) {
//如这条件成立，说明蛇头走的下一点是食物的点
console.log('撞到食物了');
this.strategies.eat.call(this);
return;
}
// 下个点什么都不是，继续走
this.strategies.move.call(this);
};
// 处理碰撞后要做的事
Snake.prototype.strategies = {
move: function(format) { //format这个参数用于决定要不要删除最后一个方块（蛇尾）,当传了这个参数就表示要做的事情是吃
//创建新身体（在旧蛇头的位置）
var newBody = new Square(this.head.x / sw, this.head.y / sh, 'snakeBody');
//更新链表的关系
newBody.next = this.head.next;
newBody.next.last = newBody;
newBody.last = null;
//把旧蛇头从原来的位置删除
this.head.remove();
newBody.create();
//创建新的蛇头（蛇头下一个要走到的点nextPos）
var newHead = new Square(this.head.x / sw + this.direction.x, this.head.y / sh + this.direction.y, 'snakeHead');
//更新链表关系
newHead.next = newBody;
newHead.last = null;
newBody.last = newHead;
newHead.viewContent.style.transform = 'rotate(' + this.direction.rotate + 'deg)';
newHead.create();
//蛇身上的每一个方块的坐标也要更新
this.pos.splice(0, 0, [this.head.x / sw + this.direction.x, this.head.y / sh + this.direction.y])
this.head = newHead; //还要把this.head的信息更新一下
if (!format) { //如果format的值为false，表示需要删除（除了吃之外的操作）
this.tail.remove();
this.tail = this.tail.last;
this.pos.pop();
}
},
eat: function() {
this.strategies.move.call(this, true);
createFood();
game.score++;
},
die: function() {
// console.log('die');
game.over();
}
}
snake = new Snake();
//创建食物
function createFood() {
//食物小方块的随机坐标
var x = null;
var y = null;
var include = true; //循环跳出的条件，true表示食物坐标在蛇身上。（需要继续循环）false表示食物的坐标不再蛇身上（不用继续循环）
while (include) {
x = Math.round(Math.random() * (td - 1));
y = Math.round(Math.random() * (tr - 1));
snake.pos.forEach(function(value) {
if (x != value[0] && y != value[1]) {
//这个条件成立说明现在随机出来的这个坐标，在蛇身上没有找到。
include = false;
}
});
}
//生成食物
food = new Square(x, y, 'food');
//存储生成食物的坐标，用于跟蛇头要走的下一坐标对比
food.pos = [x, y];
var foodDom = document.querySelector('.food');
if (foodDom) {
foodDom.style.left = x * sw + 'px';
foodDom.style.top = y * sh + 'px';
} else {
food.create();
}
}
//创建游戏逻辑
function Game() {
this.timer = null;
this.score = 0;
}
Game.prototype.init = function() {
snake.init();
// snake.getNextPos();
createFood();
var flag = true;
document.onkeydown = function(ev) {
//当蛇在往右走，不能按左键
if (ev.which == 37 && snake.direction != snake.directionNum.right) {
if (flag) {
flag = false;
setTimeout(function() {
snake.direction = snake.directionNum.left;
flag = true;
}, 150)
}
} else if (ev.which == 38 && snake.direction != snake.directionNum.down) {
if (flag) {
flag = false;
setTimeout(function() {
snake.direction = snake.directionNum.up;
flag = true;
}, 150)
}
} else if (ev.which == 39 && snake.direction != snake.directionNum.left) {
if (flag) {
flag = false;
setTimeout(function() {
snake.direction = snake.directionNum.right;
flag = true;
}, 150)
}
} else if (ev.which == 40 && snake.direction != snake.directionNum.up) {
if (flag) {
flag = false;
setTimeout(function() {
snake.direction = snake.directionNum.down;
flag = true;
}, 150)
}
}
}
this.start();
};
//开始游戏
Game.prototype.start = function() {
this.timer = setInterval(function() {
snake.getNextPos();
}, 150);
};
//暂停游戏
Game.prototype.pause = function() {
clearInterval(this.timer);
};
//游戏结束
Game.prototype.over = function() {
clearInterval(this.timer);
alert('你的得分为' + this.score);
//游戏回到初始状态
var snakeWrap = document.getElementById('snakeWrap');
snakeWrap.innerHTML = '';
snake = new Snake();
game = new Game();
var startBtnWrap = document.querySelector('.startBtn');
startBtnWrap.style.display = 'block';
};
//开启游戏
game = new Game();
var startBtn = document.querySelector('.startBtn button');
console.log(startBtn);
startBtn.onclick = function() {
startBtn.parentNode.style.display = 'none';
game.init();
};
//暂停游戏
var snakeWrap = document.getElementById('snakeWrap');
console.log(snakeWrap);
var pauseBtn = document.querySelector('.pauseBtn button');
console.log(pauseBtn);
snakeWrap.onclick = function() {
game.pause();
pauseBtn.parentNode.style.display = 'block';
console.log(123);
};
pauseBtn.onclick = function() {
game.start();
pauseBtn.parentNode.style.display = 'none';
}
})
