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演示

技术栈

今天没有什么特别要讲的，要不我们提前介绍下次要做的技术吧。你不说话就是同意了。我们开始了。 下图是正则表达式的一些总结大家可以先看看哦

(function() {
    /**
     * 1. JavaScript使用正则式的函数
     */
    const str = "abchelloasdasdhelloasd";

    // 1. 查找
    console.log(str.search("h")); // 3
    
    // 2. 替换
    console.log(str.replace(/a/, "s")); // sbchelloasdasdhelloasd
    
    // 3. 切割
    console.log(str.split(/ab/)); // ["", "bchello", "sd", "sdhello", "sd"]
    
    // 4. RegExp.prototype.test方法：检测该字符串是否包含指定串
    console.log(/hello/.test("abchello")); // true
    
    // 5. RegExp.prototype.exec方法：将满足条件的字符串放到数组
    let reg=/hello/g;
    reg.exec("abchelloasdasdhelloasd");  // ["hello"]

}());

源码

<div id='box'></div>

定义敌方战机

//敌方战机
				'enemy' : function(){
					var oEnemy = Game.ctE('img');
					oEnemy.src='images/enemy.png';
					oEnemy.className='enemy';
					Game.box.appendChild(oEnemy);
					var left = Math.random()*(Game.box.clientWidth-Game.getstyle(oEnemy,'width')/2);
					var top = Game.getstyle(oEnemy,'top');
					oEnemy.style.left=left+'px';
					oEnemy.timer=setInterval(function(){
						/*敌军下落速度*/
						top+=3;
						oEnemy.style.top=top+'px';
						if(top>Game.box.clientHeight){
							clearInterval(oEnemy.tiamr);
							if(!oEnemy.parentNode){
								return;
							}else{
								oEnemy.parentNode.removeChild(oEnemy);
							};
						}else{
							var allB = Game.getclass(Game.box,'img','bullet');
							for(var i=0;i<allB.length;i++){
								if(Game.pz(oEnemy,allB[i])){
									allB[i].parentNode.removeChild(allB[i]);
									oEnemy.src='images/boom.png';
									clearInterval(oEnemy.timer);
									setTimeout(function(){
										if(!oEnemy.parentNode){
											return;
										}else{
											oEnemy.parentNode.removeChild(oEnemy);
										};
									},500);
									Game.num+=10;
									Game.oScore.innerHTML=Game.num+'分';
									Game.fenshu=Game.oScore.innerHTML;
								};	
							};
							if(Game.pz(oEnemy,Game.oPlane)){
								oEnemy.src='images/boom.png';
								clearInterval(oEnemy.timer);
								setTimeout(function(){
									if(!oEnemy.parentNode){
										return;
									}else{
										oEnemy.parentNode.removeChild(oEnemy);
									};
								},500);
								Game.oPlane.src='images/boom2.png';
								clearInterval(Game.bTimer);
								clearInterval(Game.start.timer);
								document.onmousemove=null;
								setTimeout(function(){
									Game.over();
								},3000);
							};
						};
					},30);
				},

定义我方战机

		'plane' : function(ev,t,c){
					Game.box.appendChild(Game.oPlane);
					var bT = Game.box.offsetTop + Game.oPlane.clientHeight/2 + (Game.box.offsetHeight-Game.getstyle(Game.box,'height'))/2;
					var bL = Game.box.offsetLeft + Game.oPlane.clientWidth/2 + (Game.box.offsetWidth-Game.getstyle(Game.box,'width'))/2;
					var top = ev.pageY - bT;
					var left = ev.pageX - bL;
					Game.oPlane.style.cssText='top:'+top+'px;left:'+left+'px;';	

					var topMax = Game.getstyle(Game.box,'height')-Game.oPlane.clientHeight/2;
					var leftMin = -Game.oPlane.clientWidth/2;
					var leftMax = Game.getstyle(Game.box,'width')-Game.oPlane.clientWidth/2;
					document.onmousemove = function(ev){
						ev = ev||event;
						top = ev.pageY - bT;
						left = ev.pageX - bL;
						if(top<0){
							top=0;
						}else if(top>topMax){
							top = topMax;
						};
						if(left<leftMin){
							left = leftMin;
						}else if(left>leftMax){
							left = leftMax;
						};
						Game.oPlane.style.cssText='top:'+top+'px;left:'+left+'px;';	
					};
					
					/*子弹生成速度 */
					Game.bTimer=setInterval(function(){Game.bullet(top,left,c);},t);

				},

碰撞检测

//碰撞检测
				'pz' : function(obj1,obj2){
					var T1 = Game.getstyle(obj1,'top');
					var B1 = T1+Game.getstyle(obj1,'height');
					var L1 = Game.getstyle(obj1,'left');
					var R1 = L1+Game.getstyle(obj1,'width');

					var T2 = Game.getstyle(obj2,'top');
					var B2 = T2+Game.getstyle(obj2,'height');
					var L2 = Game.getstyle(obj2,'left');
					var R2 = L2+Game.getstyle(obj2,'width');

					if(T1>B2||L1>R2||B1<T2||R1<L2){
						return false;
					}else{
						return true;
					};
				},