课程设计:使用JavaScript制作一个网页上的贪吃蛇游戏

JavaScript021

课程设计:使用JavaScript制作一个网页上的贪吃蛇游戏,第1张

<html>

<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>

吃掉一个后 clearIntervar(变量) 然后再重新定义一个 setInterval(function(){}, 250)

var speed = 500

var go = function(){

//蛇运动的方法

if(吃到一个){

clearIntervar(_intervar )

_intervar = setsetInterval(go,speed*0.9)

}

}

var _intervar = setsetInterval(go,speed)