HTML部分
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>来玩贪吃蛇吧</title>
<style>
.map{
width: 800px;
height: 600px;
background-color: seagreen;
position: relative;
}
</style>
</head>
<body>
<div class="map"></div>
<script src="食物JS.js"></script>
<script src="贪吃蛇JS.js"></script>
<script src="游戏JS.js"></script>
<script>
var gm=new Game(document.querySelector(".map"));
gm.init();
</script>
</body>
</html>
JS部分
食物对象
//自调函数--食物
((function () {
//自定义构造函数创建对象
var elements=[];
function Food(width,height,color,x,y) {
this.width=width||20;
this.height=height||20;
this.color=color||"black";
this.x=x||0;
this.y=y||0;
}
Food.prototype.init=function (map) {
remove();
var div=document.createElement("div");
map.appendChild(div);
div.style.width=this.width+"px";
div.style.height=this.height+"px";
div.style.position="absolute";
div.style.backgroundColor=this.color;
//随机横纵坐标
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() {
for(var i=0;i<elements.length;i++){
var ele=elements[i];
ele.parentNode.removeChild(ele);
elements.splice(i,1);
}
}
window.Food=Food;
})());
贪吃蛇对象
//自调函数--贪吃蛇
((function () {
var elements=[];
function Snake(width,height,direction) {
this.width=width||20;
this.height=height||20;
//贪吃蛇的身体
this.body=[
{x:3,y:2,color:"blue"},
{x:2,y:2,color:"white"},
{x:1,y:2,color:"white"},
];
this.direction=direction||"right";
}
Snake.prototype.init=function (map) {
remove();
for(var i=0;i<this.body.length;i++){
var div=document.createElement("div");
map.appendChild(div);
var obj=this.body[i];
div.style.width=this.width+"px";
div.style.height=this.height+"px";
div.style.position="absolute";
div.style.left=obj.x*this.width+"px";
div.style.top=obj.y*this.height+"px";
div.style.backgroundColor=obj.color;
elements.push(div);
}
}
Snake.prototype.move=function (food,map) {
//身体跟着头动
var i=this.body.length-1;
//第二块的身体到第一块的位置
for(;i>0;i--){
this.body[i].x=this.body[i-1].x;
this.body[i].y=this.body[i-1].y;
}
//判断方向改变贪吃蛇头部位置的坐标
switch (this.direction){
case "left":this.body[0].x-=1;break;
case "right":this.body[0].x+=1;break;
case "top":this.body[0].y-=1;break;
case "bottom":this.body[0].y+=1;break;
}
//判断贪吃蛇是否吃到食物(若吃到食物则，贪吃蛇头部的位置与食物的位置相同)
var headX=this.body[0].x*this.width;
var headY=this.body[0].y*this.height;
if(headX==food.x&&headY==food.y){
var last=this.body[this.body.length-1];
this.body.push({
x:last.x,
y:last.y,
color:last.color,
})
food.init(map);
}
}
function remove(){
var i=elements.length-1;
for(;i>=0;i--){
var ele=elements[i];
ele.parentNode.removeChild(ele);
elements.splice(i,1);
}
}
window.Snake=Snake;
})());
游戏对象
//自调函数--游戏
((function () {
var that=null;
function Game(map) {
this.food=new Food();
this.snake=new Snake();
this.map=map;
that=this;
}
//初始化游戏
Game.prototype.init=function () {
this.food.init(this.map);
this.snake.init(this.map);
this.runSnake(this.food,this.map);
this.bindKey();
}
//让贪吃蛇自己跑起来
Game.prototype.runSnake=function (food,map) {
var timeId=setInterval(function () {
this.snake.move(food,map);
this.snake.init(map);
//移动位置的限制
var maxX=map.offsetWidth/this.snake.width;
var maxY=map.offsetHeight/this.snake.height;
//贪吃蛇头的坐标
var headX=this.snake.body[0].x;
var headY=this.snake.body[0].y;
//横纵坐标限制
if(headX<0||headX>=maxX){
clearInterval(timeId);
alert("很遗憾，游戏结束了");
};
if(headY<0||headY>=maxY){
clearInterval(timeId);
alert("很遗憾，游戏结束了");
};
//头不能撞到自己的身体（头的坐标不能等于任何一个身体部位的坐标）
var currentBody=this.snake.body.slice(1);
for(var i=5;i<currentBody.length;i++){
if(headX==currentBody[i].x&&headY==currentBody[i].y){
clearInterval(timeId);
alert("呀，撞到自己了");
}
}
}.bind(that),200)
}
//设置用户按键控制贪吃蛇移动
Game.prototype.bindKey=function(){
//阻止贪吃蛇反向
//为键盘按下注册多个事件
document.addEventListener("keydown",function (e) {
switch (e.keyCode){
case 37:this.snake.direction="left";break;
case 39:this.snake.direction="right";break;
case 38:this.snake.direction="top";break;
case 40:this.snake.direction="bottom";break;
default:;
}
}.bind(that),false);
}
window.Game=Game;
})())