【前端 js】 贪吃蛇小游戏
小游戏总共分为三个模块：1、食物 2、蛇 3、游戏对象 模块分类如下：
1、食物：
//自调用函数 初始化食物
(function() {
var elements = [];
function Food(x, y, width, height, color) {
this.x = x || 0;
this.y = y || 0;
this.width = width || 20;
this.height = height || 20;
this.color = color || "black";
}
Food.prototype.init = function(map) {
remove();
//创建div
var div = document.createElement("div");
map.appendChild(div);
div.style.width = this.width + "px";
div.style.height = this.height + "px";
div.style.backgroundColor = this.color;
div.style.position = "absolute";
this.x = parseInt(Math.random() * (map.offsetWidth / this.width)) * this.width;
this.y = parseInt(Math.random() * (map.offsetHeight / this.height)) * this.height;
div.style.left = this.x + "px";
div.style.top = this.y + "px";
elements.push(div);
}
function remove(map) {
for (var i = 0; i < elements.length; i++) {
var div = elements[i];
div.parentNode.removeChild(div);
//移除第i除的1个元素
elements.splice(i, 1);
}
}
window.Food = Food;
}());2、小蛇
//自调用函数 小蛇
(function() {
function Snake(width, height, direction) {
this.width = width || 20;
this.height = height || 20;
this.direction = direction || "right";
this.body = [{
x: 2,
y: 0,
color: "red"
}, {
x: 1,
y: 0,
color: "orange"
}, {
x: 0,
y: 0,
color: "orange"
}];
that = this;
}
var snElements = [];
Snake.prototype.init = function(map) {
//添加前先移除已经存在的内容
var j = snElements.length - 1;
for (; j >= 0; j--) {
var div = snElements[j];
div.parentNode.removeChild(div);
snElements.splice(j, 1)
}
//添加内容
for (var i = 0; i < this.body.length; i++) {
var div = document.createElement("div");
div.style.width = this.width + "px";
div.style.height = this.height + "px";
div.style.position = "absolute";
div.style.backgroundColor = this.body[i].color;
//设置横纵坐标
div.style.left = this.body[i].x * this.width + "px";
div.style.top = this.body[i].y * this.height + "px";
map.appendChild(div);
snElements.push(div);
}
};
/**
* 蛇移动与吃食物
**/
Snake.prototype.move = function(food) {
//是否吃到食物
var isNeedAdd = false;
//用于存储body边之前的内容，便于body的增减
var bodye = copy(this.body, true);
//蛇头
switch (this.direction) {
case "right":
this.body[0].x = this.body[0].x + 1;
break;
case "left":
this.body[0].x = this.body[0].x - 1;
break;
case "top":
this.body[0].y = this.body[0].y - 1;
break;
case "bottom":
this.body[0].y = this.body[0].y + 1;
break;
}
//蛇头已经位移后判断是否吃到食物
if ((this.body[0].x) * this.width == food.x && (this.body[0].y) * this.height == food.y) {
//吃到了食物
var addObj = {
x: bodye[0].x,
y: bodye[0].y,
color: bodye[1].color
}
this.body.splice(1, 0, addObj);
isNeedAdd = true;
console.log(this.body);
} else {
//移动
//蛇身
var i = this.body.length - 1;
for (; i > 0; i--) {
this.body[i].x = bodye[i - 1].x;
this.body[i].y = bodye[i - 1].y;
};
}
return isNeedAdd;
}
window.Snake = Snake;
}());3、游戏模块
//游戏对象
(function() {
var timer;
function Game(map) {
this.map = map;
this.food = new Food();
this.snake = new Snake();
that = this;
this.timer = undefined;
}
Game.prototype.init = function() {
this.snake.init(this.map);
this.getFood();
this.run();
this.keyDown();
}
Game.prototype.run = function() {
this.timer = setInterval(function() {
//移动 并判断是否吃到了食物
if (this.snake.move(this.food)) {
//吃到了刷新内容
this.getFood();
}
//超出map范围，输了
if ((this.snake.body[0].x + 1) * this.snake.width > parseInt(getStyle(this.map, "width")) ||
(this.snake.body[0].x) * this.snake.width < 0 ||
(this.snake.body[0].y + 1) * this.snake.height > parseInt(getStyle(this.map, "height")) ||
(this.snake.body[0].y) * this.snake.height < 0) {
clearTimeout(this.timer);
alert("你输了");
} else {
this.snake.init(this.map);
}
}.bind(that), 150);
}
Game.prototype.keyDown = function() {
addEventListener("keydown", function() {
var keyCode = arguments[0].keyCode;
if (keyCode == 40 || keyCode == 38) {
if (this.snake.direction == "bottom" || this.snake.direction == "top") {
return;
}
} else if (keyCode == 37 || keyCode == 39) {
if (this.snake.direction == "left" || this.snake.direction == "right") {
return;
}
} else if (keyCode == 32) {
//暂停
console.dir(this.timer);
}
switch (arguments[0].keyCode) {
//下
case 40:
this.snake.direction = "bottom";
break;
//上
case 38:
this.snake.direction = "top";
break;
//左
case 37:
this.snake.direction = "left";
break;
case 39:
this.snake.direction = "right";
break;
}
}.bind(that), false);
}
/**
* 作用 获取/生成食物
* 要求：获取或生成时蛇与食物的位置不覆盖
* **/
Game.prototype.getFood = function() {
this.food.init(this.map);
var body = this.snake.body;
for (var i = 0; i < body.length; i++) {
if (this.food.x == body.x * body.width && this.food.y == body.height * body.y) {
this.getFood();
}
}
}
window.Game = Game;
}());方法调用初始化：
var game = new Game(document.querySelector(".bg"));
game.init();
直接上源码：
贪吃蛇游戏