<head>
<title>贪吃蛇 Snake v2.4</title>
<style>
body{
font-size:9pt
}
table{
border-collapse: collapse
border:solid #333 1px
}
td{
height: 10px
width: 10px
font-size: 0px
}
.filled{
background-color:blue
}
</style>
</head>
<script>
function $(id){return document.getElementById(id)}
/**************************************************************
* javascript贪吃蛇 v2.4 <br />
* author: sunxing007 05/14/2009<br />
* 转载请注明来自http://blog.csdn.net/sunxing007 谢谢！<br />
* v2.4修正了蛇身颜色可以随着蛇前进而移动
**************************************************************/
//贪吃蛇类
var Snake = {
tbl: null,
/**
* body: 蛇身，数组放蛇的每一节，
* 数据结构{x:x0, y:y0, color:color0},
* x,y表示坐标,color表示颜色
**/
body: [],
//当前移动的方向,取值0,1,2,3, 分别表示向上,右,下,左, 按键盘方向键可以改变它
direction: 0,
//定时器
timer: null,
//速度
speed: 250,
//是否已经暂停
paused: true,
//行数
rowCount: 30,
//列数
colCount: 30,
//初始化
init: function(){
var colors = ['red','orange','yellow','green','blue','purple','#ccc']
this.tbl = $("main")
var x = 0
var y = 0
var colorIndex = 0
//产生初始移动方向
this.direction = Math.floor(Math.random()*4)
//构造table
for(var row=0row<this.rowCountrow++){
var tr=this.tbl.insertRow(-1)
for(var col=0col<this.colCountcol++) {
var td=tr.insertCell(-1)
}
}
//产生20个松散节点
for(var i=0i<10i++){
x = Math.floor(Math.random()*this.colCount)
y = Math.floor(Math.random()*this.rowCount)
colorIndex = Math.floor(Math.random()*7)
if(!this.isCellFilled(x,y)){
this.tbl.rows[y].cells[x].style.backgroundColor = colors[colorIndex]
}
}
//产生蛇头
while(true){
x = Math.floor(Math.random()*this.colCount)
y = Math.floor(Math.random()*this.rowCount)
if(!this.isCellFilled(x,y)){
this.tbl.rows[y].cells[x].style.backgroundColor = "black"
this.body.push({x:x,y:y,color:'black'})
break
}
}
this.paused = true
//添加键盘事件
document.onkeydown= function(e){
if (!e)e=window.event
switch(e.keyCode | e.which | e.charCode){
case 13: {
if(Snake.paused){
Snake.move()
Snake.paused = false
}
else{
//如果没有暂停，则停止移动
Snake.pause()
Snake.paused = true
}
break
}
case 37:{//left
//阻止蛇倒退走
if(Snake.direction==1){
break
}
Snake.direction = 3
break
}
case 38:{//up
//快捷键在这里起作用
if(event.ctrlKey){
Snake.speedUp(-20)
break
}
if(Snake.direction==2){//阻止蛇倒退走
break
}
Snake.direction = 0
break
}
case 39:{//right
if(Snake.direction==3){//阻止蛇倒退走
break
}
Snake.direction = 1
break
}
case 40:{//down
if(event.ctrlKey){
Snake.speedUp(20)
break
}
if(Snake.direction==0){//阻止蛇倒退走
break
}
Snake.direction = 2
break
}
}
}
},
//移动
move: function(){
this.timer = setInterval(function(){
Snake.erase()
Snake.moveOneStep()
Snake.paint()
}, this.speed)
},
//移动一节身体
moveOneStep: function(){
if(this.checkNextStep()==-1){
clearInterval(this.timer)
alert("Game over!\nPress Restart to continue.")
return
}
if(this.checkNextStep()==1){
var _point = this.getNextPos()
var _x = _point.x
var _y = _point.y
var _color = this.getColor(_x,_y)
this.body.unshift({x:_x,y:_y,color:_color})
//因为吃了一个食物，所以再产生一个食物
this.generateDood()
return
}
//window.status = this.toString()
var point = this.getNextPos()
//保留第一节的颜色
var color = this.body[0].color
//颜色向前移动
for(var i=0i<this.body.length-1i++){
this.body[i].color = this.body[i+1].color
}
//蛇尾减一节， 蛇尾加一节，呈现蛇前进的效果
this.body.pop()
this.body.unshift({x:point.x,y:point.y,color:color})
//window.status = this.toString()
},
//探寻下一步将走到什么地方
pause: function(){
clearInterval(Snake.timer)
this.paint()
},
getNextPos: function(){
var x = this.body[0].x
var y = this.body[0].y
var color = this.body[0].color
//向上
if(this.direction==0){
y--
}
//向右
else if(this.direction==1){
x++
}
//向下
else if(this.direction==2){
y++
}
//向左
else{
x--
}
//返回一个坐标
return {x:x,y:y}
},
//检查将要移动到的下一步是什么
checkNextStep: function(){
var point = this.getNextPos()
var x = point.x
var y = point.y
if(x<0||x>=this.colCount||y<0||y>=this.rowCount){
return -1//触边界，游戏结束
}
for(var i=0i<this.body.lengthi++){
if(this.body[i].x==x&&this.body[i].y==y){
return -1//碰到自己的身体,游戏结束
}
}
if(this.isCellFilled(x,y)){
return 1//有东西
}
return 0//空地
},
//擦除蛇身
erase: function(){
for(var i=0i<this.body.lengthi++){
this.eraseDot(this.body[i].x, this.body[i].y)
}
},
//绘制蛇身
paint: function(){
for(var i=0i<this.body.lengthi++){
this.paintDot(this.body[i].x, this.body[i].y,this.body[i].color)
}
},
//擦除一节
eraseDot: function(x,y){
this.tbl.rows[y].cells[x].style.backgroundColor = ""
},
paintDot: function(x,y,color){
this.tbl.rows[y].cells[x].style.backgroundColor = color
},
//得到一个坐标上的颜色
getColor: function(x,y){
return this.tbl.rows[y].cells[x].style.backgroundColor
},
//用于调试
toString: function(){
var str = ""
for(var i=0i<this.body.lengthi++){
str += "x:" + this.body[i].x + " y:" + this.body[i].y + " color:" + this.body[i].color + " - "
}
return str
},
//检查一个坐标点有没有被填充
isCellFilled: function(x,y){
if(this.tbl.rows[y].cells[x].style.backgroundColor == ""){
return false
}
return true
},
//重新开始
restart: function(){
if(this.timer){
clearInterval(this.timer)
}
for(var i=0i<this.rowCounti++){
this.tbl.deleteRow(0)
}
this.body = []
this.init()
this.speed = 250
},
//加速
speedUp: function(time){
if(!this.paused){
if(this.speed+time<10||this.speed+time>2000){
return
}
this.speed +=time
this.pause()
this.move()
}
},
//产生食物。
generateDood: function(){
var colors = ['red','orange','yellow','green','blue','purple','#ccc']
var x = Math.floor(Math.random()*this.colCount)
var y = Math.floor(Math.random()*this.rowCount)
var colorIndex = Math.floor(Math.random()*7)
if(!this.isCellFilled(x,y)){
this.tbl.rows[y].cells[x].style.backgroundColor = colors[colorIndex]
}
}
}
</script>
<body onload="Snake.init()">
/*************************************************************<br />
* javascript贪吃蛇 v2.4<br />
* author: sunxing007 05/14/2009<br />
* 转载请注明来自 <a href="http://blog.csdn.net/sunxing007">http://blog.csdn.net/sunxing007</a>谢谢！<br />
**************************************************************/<br />
<table id="main" border="1" cellspacing="0" cellpadding="0"></table>
<input type="button" id="btn" value="开始/暂停" />点左边按钮或按Enter开始/暂停游戏<br />
<input type="button" id="reset" value="重新开始" /><br />
<input type="button" id="upSpeed" value="加速" />点左边按钮或按Ctrl + ↑加速<br />
<input type="button" id="downSpeed" value="减速" />点左边按钮或按Ctrl + ↓减速
<script>
$('btn').onclick = function(){
if(Snake.paused){
Snake.move()
Snake.paused = false
}
else{
Snake.pause()
Snake.paused = true
}
}
$("reset").onclick = function(){
Snake.restart()
this.blur()
}
$("upSpeed").onclick = function(){
Snake.speedUp(-20)
}
$("downSpeed").onclick = function(){
Snake.speedUp(20)
}
</script>
</body>
</html>
