面向对象 小游戏 打飞机

<style>
			#mainBox{
				overflow:hidden;
				position:relative;
				320px;
				height:568px;
				background:url(images/background_1.png) no-repeat;
				margin:30px auto 0;
			}
		</style>

　　

<div id="mainBox"></div>
		<script type="text/javascript" src="js/main1.js"></script>

　　js/main1.js

var mainBox = document.getElementById("mainBox");//获取主界面
var ourPlane = new myPlane(0,0);//创建本飞机对象实例
ourPlane.createPlane("selfPlane");//调用创建本方飞机方法 并且传入本方飞机节点ID名
var selfPlane = document.getElementById("selfPlane");//获取本方飞机节点
ourPlane.shoot();//调用本方飞机的射击方法
mainBox.onmousemove = function(e){
	var e = event||window.event;
	var oLeft = e.clientX - mainBox.offsetLeft - selfPlane.offsetWidth/2;
	var oTop = e.clientY - mainBox.offsetTop - selfPlane.offsetHeight/2;
	if(oLeft<=0){
		oLeft=0;
	}
	if(oLeft>=(mainBox.offsetWidth-selfPlane.offsetWidth)){
		oLeft = mainBox.offsetWidth-selfPlane.offsetWidth;
	}
	if(oTop<=0){
		oTop=0;
	}
	if(oTop>=(mainBox.offsetHeight-selfPlane.offsetHeight)){
		oTop = mainBox.offsetHeight-selfPlane.offsetHeight;
	}
	selfPlane.style.left = oLeft + "px";
	selfPlane.style.top = oTop + "px";
	mainBox.style.cursor = "none";
}
mainBox.onmouseout = function(){
	mainBox.style.cursor = "";
}
function plane(x,y,hp,imgsrc,speed){
	this.planex = x;
	this.planey = y;
	this.planeSpeed = speed;
	this.hp = hp;
	this.imgsrc = imgsrc;
	this.createPlane = function(id){
		this.planeNode = document.createElement("img");
		if(id){
			this.planeNode.id = id
		}		
		this.planeNode.src = this.imgsrc;
		this.planeNode.style.left = this.planex+"px";
		this.planeNode.style.top = this.planey+"px";
		this.planeNode.style.position = "absolute";
		mainBox.appendChild(this.planeNode);
		if(this.planeSpeed!=0){
			this.move();
		}		
	}
	this.move = function(){
		var that = this;
		var step = 0;
		this.time = setInterval(function(){
			var bullets = document.getElementsByClassName("bullets");
			step += that.planeSpeed;
			that.planeNode.style.top = step + "px";
			for(var i=0;i<bullets.length;i++){
				if((parseInt(that.planeNode.style.left)<=parseInt(bullets[i].style.left))&&((parseInt(that.planeNode.style.left)+that.planeNode.offsetWidth)>=parseInt(bullets[i].style.left))&&((parseInt(that.planeNode.style.top)+that.planeNode.offsetHeight)>=parseInt(bullets[i].style.top))){
					that.hp--;
					bullets[i].parentNode.removeChild(bullets[i]);
				}
			}
			if(that.hp<=0){
				clearInterval(that.time);
				that.planeNode.parentNode.removeChild(that.planeNode);
			}else if(parseInt(that.planeNode.style.top) >= mainBox.offsetHeight+that.planeNode.offsetHeight){
				clearInterval(that.time);
				that.planeNode.parentNode.removeChild(that.planeNode);
			}
		},50)
	}
}
function myPlane(X,Y){
	plane.call(this,X,Y,1,"images/我的飞机.gif",0);
	this.shoot = function(){
		this.time = setInterval(function(){
			oLeft  = parseInt(selfPlane.style.left)+selfPlane.offsetWidth/2+"px";
			oTop = selfPlane.style.top;
			var myBullet = new bullet(oLeft,oTop);
			myBullet.createBullet();
		},100)
	}	
	this.createEnemy = function(){
		var that = this;
		function enemy(X,Y,hp,imgsrc,speed){
			plane.call(this,X,Y,hp,imgsrc,speed);	
		}
		this.time1 = setInterval(function(){
			for(var i=0;i<randomNum(1,3);i++){
				var num = randomNum(1,10);
				if(num<=6){
					num = 1;
				}else if(num>6&&num<=9){
					num = 2;
				}else{
					num = 3;
				}
				var createX = [randomNum(16,270),randomNum(0,274),randomNum(0,210)];
				var imgsrc = "images/enemy"+num+"_fly_1.png";
				var enemyPlane = new enemy(createX[num-1],0,Math.pow(num,2),imgsrc,(1/num)*6);
				enemyPlane.createPlane();
			}
		},2000)
	}
	this.createEnemy();
}
function bullet(X,Y){
	this.bulletx = X;
	this.bullety = Y;
	this.createBullet = function(){
		this.bulletNode = document.createElement("img");
		this.bulletNode.src = "images/bullet1.png";
		this.bulletNode.className = "bullets";
		this.bulletNode.style.position = "absolute";
		this.bulletNode.style.left = this.bulletx;
		this.bulletNode.style.top = this.bullety;
		mainBox.appendChild(this.bulletNode);
		this.move();
	}
	this.move = function(){
		var speed = 2;
		var that = this;
		this.time = setInterval(function(){
			var step = 0;
			step -= speed;
			that.bulletNode.style.top = parseInt(that.bulletNode.style.top) + step + "px";
			if(parseInt(that.bulletNode.style.top)<=0){
				clearInterval(that.time);
				that.bulletNode.parentNode.removeChild(that.bulletNode);
			}
		},1)
	}
}

function randomNum(min,max){
	return Math.floor(Math.random()*max+min);
}