JS用原型对象写的贪吃蛇，很粗糙的代码

摘要：贪吃蛇类默识贪吃蛇速度，毫秒地图轴分为多少单位地图轴分为多少单位贪吃蛇运动速度贪吃蛇每节身体和食物的宽高地图轴分为多少单位初始化贪吃蛇属性蛇移动方向食物和食物的坐标游戏开始创建地图初始化食物初始化贪吃蛇绑定键盘方向更改贪吃蛇方向移动贪吃蛇创

/**

贪吃蛇类

@author 默识

@param {int} speed 贪吃蛇速度，毫秒

@param {int} x 地图x轴分为多少单位

@param {int} y 地图y轴分为多少单位

@returns {Snake} none
*/

function Snake(speed, x, y) {

//贪吃蛇运动速度
this.speed = speed;
//贪吃蛇每节身体和食物的宽高
this.width = window.innerWidth / x;
this.height = window.innerHeight / y;
//地图xy轴分为多少单位
this.x = x;
this.y = y;
//初始化贪吃蛇属性
this.sBody = [
    [0, 1, "green"],
    [1, 1, "green"],
    [2, 1, "green"],
    [3, 1, "red"]
];
//蛇移动方向
this.sDirection = "right";
//食物和食物的坐标
this.food = null;
this.foodX = 0;
this.foodY = 0;

}
/**

游戏开始

@returns {undefined} none
*/

Snake.prototype.start = function () {

this.createMap();//创建地图
this.createFood();//初始化食物
this.createSnake();//初始化贪吃蛇
this.bind();//绑定键盘方向更改贪吃蛇方向
//移动贪吃蛇
setInterval(function () {
    snake.moveSnake();
}, this.speed);

};
/**

创建贪吃蛇地图

@returns {undefined}none
*/

Snake.prototype.createMap = function () {

document.body.style.backgroundColor = "black";

};
/**

创建贪吃蛇食物

@returns {undefined}none
*/

Snake.prototype.createFood = function () {

//创建食物
var food = document.createElement("div");
this.food = food;
this.foodX = Math.floor(Math.random() * this.x);
this.foodY = Math.floor(Math.random() * this.y);
//食物的样式
with (food.style) {
    position = "absolute";
    width = this.width + "px";
    height = this.height + "px";
    backgroundColor = "green";
    left = this.foodX * this.width + "px";//食物随机X轴坐标
    top = this.foodY * this.height + "px";//食物随机Y轴坐标  
}
//食物添加到地图上
document.body.appendChild(food);

};
/**

创建贪吃蛇

@returns {undefined}none
*/

Snake.prototype.createSnake = function () {

//绘制蛇
for (var i = 0; i < this.sBody.length; i++) {
    this.sBody[i][3] = this.sBody[i][3] || document.createElement("div");
    //设置蛇的样式
    with (this.sBody[i][3].style) {
        position = "absolute";
        width = this.width + "px";
        height = this.height + "px";
        left = this.sBody[i][0] * this.width + "px";
        top = this.sBody[i][1] * this.height + "px";
        backgroundColor = this.sBody[i][2];
    }
    //放入地图中
    document.body.appendChild(this.sBody[i][3]);
}

};
/**

绑定方向事件更改贪吃蛇运动方向

@returns {undefined}none
*/

Snake.prototype.bind = function () {

var tmp = this;
document.onkeyup = function (e) {
    var e = window.event || e;
    switch (e.keyCode) {
        case 37:
            tmp.sDirection = "left";
            break;
        case 38:
            tmp.sDirection = "up";
            break;
        case 39:
            tmp.sDirection = "right";
            break;
        case 40:
            tmp.sDirection = "down";
            break;
    }
}

};
/**

贪吃蛇行动

@returns {undefined}none
*/

Snake.prototype.moveSnake = function () {

//舍身跟随前一节运动,即改变坐标，注意蛇身先走，要不蛇头紧随的一段身体会跟蛇头重叠
for (var i = 0; i < this.sBody.length - 1; i++) {
    this.sBody[i][0] = this.sBody[i + 1][0];
    this.sBody[i][1] = this.sBody[i + 1][1];
}
//蛇运动根据方向改变xy轴坐标
switch (this.sDirection) {
    case "up":
        this.sBody[this.sBody.length - 1][1]--;
        break;
    case "right":
        this.sBody[this.sBody.length - 1][0]++;
        break;
    case "down":
        this.sBody[this.sBody.length - 1][1]++;
        break;
    case "left":
        this.sBody[this.sBody.length - 1][0]--;
        break
}
//贪吃蛇吃食物
if (this.sBody[this.sBody.length - 1][0] === this.foodX
        && this.sBody[this.sBody.length - 1][1] === this.foodY
        ) {
    //创建一节身体
    var node = [this.sBody[0][0], this.sBody[0][1], "green"];
    //身体生长
    this.sBody.unshift(node);
    //食物位置重置
    this.foodX = Math.floor(Math.random() * this.x);
    this.foodY = Math.floor(Math.random() * this.y);
    with (this.food.style) {
        left = this.foodX * this.width + "px";//食物随机X轴坐标
        top = this.foodY * this.height + "px";//食物随机Y轴坐标  
    }
}
//判断游蛇是否碰到边界
if (this.sBody[this.sBody.length - 1][0] < 0
        || this.sBody[this.sBody.length - 1][0] >= this.x
        || this.sBody[this.sBody.length - 1][1] < 0
        || this.sBody[this.sBody.length - 1][1] >= this.y
        ) {
    this.gameover();
    return;
}
//显示新贪吃蛇位置
this.createSnake();

};
/**

游戏结束

@returns {undefined} none
*/

Snake.prototype.gameover = function () {

alert("GAME OVER!");
location.reload();

};
var snake = new Snake(100, 60, 40);
snake.start();