JS实现贪吃蛇游戏
作者：zoyoy
这篇文章主要介为大家详细绍了JS实现贪吃蛇小游戏，文中示例代码介绍的非常详细，具有一定的参考价值，感兴趣的小伙伴们可以参考一下
本文实例为大家分享了JS实现贪吃蛇游戏的具体代码，供大家参考，具体内容如下
html部分：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"> <link rel="stylesheet" href="./css/index.css" rel="external nofollow" > <title>贪吃蛇小游戏</title> </head> <body> <div class="content"> <div class="btn startBtn"><button></button></div> <div class="btn pauseBtn"><button></button></div> <div id="snakeWrap"> </div> </div> <script src="./js/index.js"></script> </body> </html>
css部分：
.content{
width: 640px;
height: 640px;
margin: 50px auto;
position: relative;
}
.btn{
width: 100%;
height: 100%;
position: absolute;
left: 0;
top: 0;
background-color: rgba(0,0,0,0);
z-index: 1;
}
.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: 150px;
background-image: url('../images/btn1.gif');
margin-left: -100px;
margin-top: -75px;
}
.pauseBtn{
display: none;
}
.pauseBtn button{
width: 70px;
height: 70px;
background-image: url('../images/btn4.png');
margin-left: -35px;
margin-top: -35px;
}
#snakeWrap{
position: relative;
width: 600px;
height: 600px;
background: #FCE4EC;
border: 20px solid #F8BBD0;
}
.snakeHead{
background-image: url('../images/snake.png');
background-size: cover;
}
.snakeBody{
background-color: #9CCC65;
border-radius: 50%;
}
.food{
background: url('../images/food2.png') no-repeat;
background-size: 100% 100%;
}
js部分：
var sw = 20, // 一个方块的宽度
sh = 20, // 高度
tr = 30, // 行数
td = 30; // 列数
var snake = null, // 蛇的实例
food = null, // 食物的实例
game = null; // 游戏实例
// 方块构造函数
function Square(x,y,classname) {
this.x = x*sw;
this.y = y*sh;
this.class = classname;
this.viewContent = document.createElement('div');
this.viewContent.className = this.class;
this.parent = document.getElementById('snakeWrap');
}
Square.prototype.create = function(){ // 创建方块dom
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; //蛇头
this.tail = null; // 蛇尾
this.pos = []; // 存储蛇身上的每一个方块的位置
this.directionNum = { // 存储蛇走的方向，用一个对象来表示
left:{
x:-1,
y:0,
rotate:180 // 蛇头旋转角度
},
right:{
x:1,
y:0,
rotate:0
},
up:{
x:0,
y:-1,
rotate:-90
},
down:{
x:0,
y:1,
rotate:90
}
}
}
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]) // 存储蛇头位置
// 创建蛇身体
var snakeBody1 = new Square(1,0,'snakeBody');
snakeBody1.create();
this.pos.push([1,0]) // 存储蛇身1位置
var snakeBody2 = new Square(0,0,'snakeBody');
snakeBody2.create();
this.tail = snakeBody2; // 存储蛇尾信息
this.pos.push([0,0]) // 存储蛇身1位置
// 形成链表关系
snakeHead.last = null;
snakeHead.next = snakeBody1;
snakeBody1.last = snakeHead;
snakeBody1.next = snakeBody2;
snakeBody2.last = snakeBody1;
snakeBody2.next = null;
// 给蛇添加一个属性，用来表示蛇走的方向
this.direction = this.directionNum.right; // 默认往右走
}
// 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 = [
this.head.x/sw+this.direction.x,
this.head.y/sh+this.direction.y
]
// 下个点是自己，游戏结束
var selfCollied = false; //是否撞到了自己
this.pos.forEach(function(value) {
if(value[0]==nextPos[0] && value[1]==nextPos[1]){
selfCollied = true;
}
});
if(selfCollied){
console.log('撞到了自己');
this.strategies.die.call(this);
return;
}
// 下个点是围墙，游戏结束
if(nextPos[0]<0 || nextPos[1]<0 || nextPos[0]>td-1 || nextPos[1]>tr-1){
console.log('撞到了墙');
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]){
// 如果这个条件成立说明现在蛇头要走的下一个点是食物的那个点；
console.log('吃到食物了');
this.strategies.eat.call(this);
return;
}
// 下个点什么都不是，走
this.strategies.move.call(this);
};
// 处理碰撞后要做的事
Snake.prototype.strategies = {
move:function(format) { // 该参数用于决定是否删除蛇尾
// 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;
this.head.remove(); // 把旧蛇头从原来的位置删除
newBody.create();
// 创建蛇头:蛇头下一个点
var newHead = new Square(this.head.x/sw+this.direction.x,this.head.y/sh+this.direction.y,'snakeHead');
// 更新链表的关系
newHead.next = newBody;
newHead.last = null;
newBody.last = newHead;
newHead.viewContent.style.transform = 'rotate('+this.direction.rotate+'deg)';
newHead.create();
// 更新蛇身上每一个方块的坐标
this.pos.splice(0,0,[this.head.x/sw+this.direction.x,this.head.y/sh+this.direction.y]);
this.head = newHead; //更新this.head
if(!format){ // false: 需要删除（处理吃之外的操作）
this.tail.remove();
this.tail = this.tail.last;
this.pos.pop();
}
},
eat:function(){
this.strategies.move.call(this,true);
createFood();
game.score++;
},
die:function(){
game.over();
}
}
snake = new Snake();
// snake.init();
// 创建食物
function createFood(){
// 食物的随机坐标
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，false:表示不在
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]){
// 坐标不在蛇身上
include = false;
}
})
// 生成食物
food = new Square(x,y,'food');
food.pos = [x,y]; // 存储食物的坐标，用于跟蛇头下一个走的点作对比
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();
createFood();
document.onkeydown = function(ev) {
// 用户按下左键， 蛇不能是正在往右走的
if(ev.which == 37 && snake.direction != snake.directionNum.right){
snake.direction = snake.directionNum.left;
}else if(ev.which == 38 && snake.direction != snake.directionNum.down){
snake.direction = snake.directionNum.up;
}else if(ev.which == 39 && snake.direction != snake.directionNum.left){
snake.direction = snake.directionNum.right;
}else if(ev.which == 40 && snake.direction != snake.directionNum.up){
snake.direction = snake.directionNum.down;
}
}
this.start();
}
Game.prototype.start = function(){
// 开始游戏
this.timer = setInterval(function(){
snake.getNextPos();
},200);
}
Game.prototype.pause = function() {
clearInterval(this.timer);
}
Game.prototype.over = function() {
clearInterval(this.timer);
alert('你的得分为：'+ this.score);
// 游戏回到最初始的状态
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');
startBtn.onclick = function(){
startBtn.parentNode.style.display = 'none';
game.init();
}
// 暂停游戏
var snakeWrap = document.getElementById('snakeWrap');
var pauseBtn = document.querySelector('.pauseBtn button');
snakeWrap.onclick = function() {
game.pause();
pauseBtn.parentNode.style.display='block';
}
pauseBtn.onclick = function() {
game.start();
pauseBtn.parentNode.style.display='none';
}
游戏截图：
更多关于Js游戏的精彩文章，请查看专题： 《JavaScript经典游戏 玩不停》
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。