• 用canvas整个打飞机游戏


      声明:本文为原创文章,如需转载,请注明来源WAxes,谢谢!

      之前在当耐特的DEMO里看到个打飞机的游戏,然后就把他的图片和音频扒了了下来。。。。自己凭着玩的心情重新写了一个。仅供娱乐哈。。。。。。我没有用框架,所有js都是自己写的。。。。。。所以就可以来当个简单的教程,对那些刚玩canvas的,或许能有些帮助,楼主玩canvas也不是很久,技术不是很好,请见谅哈。

      闲话不多说,先上DEMO撒:飞机游戏   楼主写这个人纯碎娱乐,没想着写成多正式的游戏哈。

      步入主题啦:打飞机游戏文件有index.html入口文件,allSprite.js精灵的逻辑处理文件,loading.js加载处理文件以及data.js(初始化的一些数据)。

      首先,正常的游戏基本上都需要一个loading,loading页面就是用来预加载数据的,包括精灵表图片,音频等,因为这是个小游戏,要加载的就只有一些音频和图片。里面的加载代码主要就下面这些,其他是制作loading动画的,那个比较简单,就不贴了,如果有兴趣的直接在DEMO里看控制台就行了:

    loadImg:function(datas){
                var _this = this;
                var dataIndex = 0;
                li();
                function li(){
                    if(datas[dataIndex].indexOf("mp3")>=0){
                        var audio = document.createElement("audio");
                        document.body.appendChild(audio);
                        audio.preload = "auto";
                        audio.src = datas[dataIndex];
                        audio.oncanplaythrough = function(){
                            this.oncanplaythrough = null;
                            dataIndex++;
                            if(dataIndex===datas.length){
                                _this.percent = 100;
                            }else {
                                _this.percent = parseInt(dataIndex/datas.length*100);
                                li.call(_this);
                            }
                        }
                    }else {
                        preLoadImg(datas[dataIndex] , function(){
                            dataIndex++;
                            if(dataIndex===datas.length){
                                _this.percent = 100;
                            } else {
                                _this.percent = parseInt(dataIndex/datas.length*100);
                                li.call(_this);
                            }
                        })
                    }
                }
            },
    
    //再贴出preLoadImg的方法
    function preLoadImg(src , callback){
        var img = new Image();
        img.src = src;
        if(img.complete){
            callback.call(img);
        }else {
            img.onload = function(){
                callback.call(img);
            }
        }
    }

    我先在data.js里面用一个数组保存文件的链接,然后判断这些链接是图片还是音频,如果是图片就用preLoadImg加载,预加载图片的代码很简单,就是new一个图片对象,然后把链接赋给它,加载完后再回调。音频的加载则是通过生成一个HTML5的audio dom对象,把链接赋给它,audio有一个事件“canplaythrough”,浏览器预计能够在不停下来进行缓冲的情况下持续播放指定的音频/视频时,会发生 canplaythrough 事件,也就是说当canplaythrough被调用时,音频就已经被加载的差不多了,可以进行下一个音频的加载了。就这样当把所有东西都加载完后,再进行回调,开始游戏。

      游戏开始了,一个游戏,会需要很多的对象,所以我就统一写成了一个精灵对象,不同对象之间的每一帧的运动情况直接用behavior来分别编写就行了。

        W.Sprite = function(name , painter , behaviors , args){
            if(name !== undefined) this.name = name;
            if(painter !== undefined) this.painter = painter;
            this.top = 0;
            this.left = 0;
            this.width = 0;
            this.height = 0;
            this.velocityX = 3;
            this.velocityY = 2;
            this.visible = true;
            this.animating = false;
            this.behaviors = behaviors;
            this.rotateAngle = 0;
            this.blood = 50;
            this.fullBlood = 50;
            if(name==="plan"){
                this.rotateSpeed = 0.05;
                this.rotateLeft = false;
                this.rotateRight = false;
                this.fire = false;
                this.firePerFrame = 10;
                this.fireLevel = 1;
            }else if(name==="star"){
                this.width = Math.random()*2;
                this.speed = 1*this.width/2;
                this.lightLength = 5;
                this.cacheCanvas = document.createElement("canvas");
                this.cacheCtx = this.cacheCanvas.getContext('2d');
                this.cacheCanvas.width = this.width+this.lightLength*2;
                this.cacheCanvas.height = this.width+this.lightLength*2;
                this.painter.cache(this);
            }else if(name==="badPlan"){
                this.badKind = 1;
                this.speed = 2;
                this.rotateAngle = Math.PI;
            }else if(name==="missle"){
                this.width = missleWidth;
            }else if(name==="boom"){
                this.width = boomWidth;
            }else if(name==="food"){
                this.width = 40;
                this.speed = 3;
                this.kind = "LevelUP"
            }
            this.toLeft = false;
            this.toTop = false;
            this.toRight = false;
            this.toBottom = false;
    
            this.outArcRadius = Math.sqrt((this.width/2*this.width/2)*2);
    
            if(args){
                for(var arg in args){
                    this[arg] = args[arg];
                }
            }
        }
        Sprite.prototype = {
            constructor:Sprite,
            paint:function(){
                if(this.name==="badPlan"){this.update();}
    
                if(this.painter !== undefined && this.visible){
                    if(this.name!=="badPlan") {
                        this.update();
                    }
                    if(this.name==="plan"||this.name==="missle"||this.name==="badPlan"){
                        ctx.save();
                        ctx.translate(this.left , this.top);
                        ctx.rotate(this.rotateAngle);
                        this.painter.paint(this);
                        ctx.restore();
                    }else {
                        this.painter.paint(this);
                    }
                }
            },
            update:function(time){
                if(this.behaviors){
                    for(var i=0;i<this.behaviors.length;i++){
                        this.behaviors[i].execute(this,time);
                    }
                }
            }
        }

    写出精灵类后,就可以通过编写每个的painter以及behavior来生成不同的对象了。接下来就是写painter了,painter分成两种,一种是普通的painter,一种就是精灵表painter,因为像爆炸动画,飞机开枪动画,都不是一张图片就能搞定的,所以就需要用到精灵表了:

    而绘制这些就要为他们定制一个精灵表绘制器,下面这个是最简单的精灵表绘制器,针对游戏的复杂性可以相对的修改精灵表写法,直到合适,不过原理都大同小异,就是小修小改而已:

    var SpriteSheetPainter = function(cells){
                this.cells = cells || [];
                this.cellIndex = 0;
            }
            SpriteSheetPainter.prototype = {
                advance:function(){
                    if(this.cellIndex === this.cells.length-1){
                        this.cellIndex = 0;
                    }
                    else this.cellIndex++;
                },
                paint:function(sprite){
                    var cell = this.cells[this.cellIndex];
                    context.drawImage(spritesheet , cell.x , cell.y , cell.w , cell.h , sprite.left , sprite.top , cell.w , cell.h);
                }
            }

    而普通的绘制器就更简单了,直接写一个painter,把要画的什么东西都写进去就行了。

    有了精灵类和精灵表绘制器后,我们就可以把星星,飞机,子弹,爆炸对象都写出来了:下面是整个allSprite.js的代码:

    (function(W){
        "use strict"
        var planWidth = 24,
            planHeight = 24,
            missleWidth = 70,
            missleHeight = 70,
            boomWidth = 60;
        //精灵类
        W.Sprite = function(name , painter , behaviors , args){
            if(name !== undefined) this.name = name;
            if(painter !== undefined) this.painter = painter;
            this.top = 0;
            this.left = 0;
            this.width = 0;
            this.height = 0;
            this.velocityX = 3;
            this.velocityY = 2;
            this.visible = true;
            this.animating = false;
            this.behaviors = behaviors;
            this.rotateAngle = 0;
            this.blood = 50;
            this.fullBlood = 50;
            if(name==="plan"){
                this.rotateSpeed = 0.05;
                this.rotateLeft = false;
                this.rotateRight = false;
                this.fire = false;
                this.firePerFrame = 10;
                this.fireLevel = 1;
            }else if(name==="star"){
                this.width = Math.random()*2;
                this.speed = 1*this.width/2;
                this.lightLength = 5;
                this.cacheCanvas = document.createElement("canvas");
                this.cacheCtx = this.cacheCanvas.getContext('2d');
                this.cacheCanvas.width = this.width+this.lightLength*2;
                this.cacheCanvas.height = this.width+this.lightLength*2;
                this.painter.cache(this);
            }else if(name==="badPlan"){
                this.badKind = 1;
                this.speed = 2;
                this.rotateAngle = Math.PI;
            }else if(name==="missle"){
                this.width = missleWidth;
            }else if(name==="boom"){
                this.width = boomWidth;
            }else if(name==="food"){
                this.width = 40;
                this.speed = 3;
                this.kind = "LevelUP"
            }
            this.toLeft = false;
            this.toTop = false;
            this.toRight = false;
            this.toBottom = false;
    
            this.outArcRadius = Math.sqrt((this.width/2*this.width/2)*2);
    
            if(args){
                for(var arg in args){
                    this[arg] = args[arg];
                }
            }
        }
        Sprite.prototype = {
            constructor:Sprite,
            paint:function(){
                if(this.name==="badPlan"){this.update();}
    
                if(this.painter !== undefined && this.visible){
                    if(this.name!=="badPlan") {
                        this.update();
                    }
                    if(this.name==="plan"||this.name==="missle"||this.name==="badPlan"){
                        ctx.save();
                        ctx.translate(this.left , this.top);
                        ctx.rotate(this.rotateAngle);
                        this.painter.paint(this);
                        ctx.restore();
                    }else {
                        this.painter.paint(this);
                    }
                }
            },
            update:function(time){
                if(this.behaviors){
                    for(var i=0;i<this.behaviors.length;i++){
                        this.behaviors[i].execute(this,time);
                    }
                }
            }
        }
    
        // 精灵表绘制器
        W.SpriteSheetPainter = function(cells , isloop , endCallback , spritesheet){
            this.cells = cells || [];
            this.cellIndex = 0;
            this.dateCount = null;
            this.isloop = isloop;
            this.endCallback = endCallback;
            this.spritesheet = spritesheet;
        }
        SpriteSheetPainter.prototype = {
            advance:function(){
                this.cellIndex = this.isloop?(this.cellIndex===this.cells.length-1?0:this.cellIndex+1):(this.cellIndex+1);
            },
            paint:function(sprite){
                if(this.dateCount===null){
                    this.dateCount = new Date();
                }else {
                    var newd = new Date();
                    var tc = newd-this.dateCount;
                    if(tc>40){
                        this.advance();
                        this.dateCount = newd;
                    }
                }
                if(this.cellIndex<this.cells.length || this.isloop){
                    var cell = this.cells[this.cellIndex];
                    ctx.drawImage(this.spritesheet , cell.x , cell.y , cell.w , cell.h , sprite.left-sprite.width/2 , sprite.top-sprite.width/2 , cell.w , cell.h);
                } else if(this.endCallback){
                    this.endCallback.call(sprite);
                    this.cellIndex = 0;
                }
            }
        }
    
        //特制飞机精灵表绘制器
        W.controllSpriteSheetPainter = function(cells , spritesheet){
            this.cells = cells || [];
            this.cellIndex = 0;
            this.dateCount = null;
            this.isActive = false;
            this.derection = true;
            this.spritesheet = spritesheet;
        }
        controllSpriteSheetPainter.prototype = {
            advance:function(){
                if(this.isActive){
                    this.cellIndex++;
                    if(this.cellIndex === this.cells.length){
                        this.cellIndex = 0;
                        this.isActive = false;
                    }
                }
            },
            paint:function(sprite){
                if(this.dateCount===null){
                    this.dateCount = new Date();
                }else {
                    var newd = new Date();
                    var tc = newd-this.dateCount;
                    if(tc>sprite.firePerFrame){
                        this.advance();
                        this.dateCount = newd;
                    }
                }
                var cell = this.cells[this.cellIndex];
                ctx.drawImage(this.spritesheet , cell.x , cell.y , cell.w , cell.h , -planWidth/2 , -planHeight/2 , cell.w , cell.h);
            }
        }
    
        W.planBehavior = [
            {execute:function(sprite,time){
                if(sprite.toTop){
                    sprite.top = sprite.top<planHeight/2? sprite.top : sprite.top-sprite.velocityY;
                }
                if(sprite.toLeft){
                    sprite.left = sprite.left<planWidth/2? sprite.left : sprite.left-sprite.velocityX;
                }
                if(sprite.toRight){
                    sprite.left = sprite.left>canvas.width-planWidth/2? sprite.left : sprite.left+sprite.velocityX;
                }
                if(sprite.toBottom){
                    sprite.top = sprite.top>canvas.height-planHeight/2? sprite.top : sprite.top+sprite.velocityY;
                }
                if(sprite.rotateLeft){
                    sprite.rotateAngle -= sprite.rotateSpeed;
                }
                if(sprite.rotateRight){
                    sprite.rotateAngle += sprite.rotateSpeed;
                }
                if(sprite.fire&&!sprite.painter.isActive){
                    sprite.painter.isActive = true;
                    this.shot(sprite);
    
                }
            },
            shot:function(sprite){
                this.addMissle(sprite , sprite.rotateAngle);
                var missleAngle = 0.1
                for(var i=1;i<sprite.fireLevel;i++){
                    this.addMissle(sprite , sprite.rotateAngle-i*missleAngle);
                    this.addMissle(sprite , sprite.rotateAngle+i*missleAngle);
                }
    
                var audio = document.getElementsByTagName("audio");
                for(var i=0;i<audio.length;i++){
                    console.log(audio[i].paused)
                    if(audio[i].src.indexOf("shot")>=0&&audio[i].paused){
                        audio[i].play();
                        break;
                    }
                }
            },
            addMissle:function(sprite , angle){
                    for(var j=0;j<missles.length;j++){
                        if(!missles[j].visible){
                            missles[j].left = sprite.left;
                            missles[j].top = sprite.top;
                            missles[j].rotateAngle = angle;
                            var missleSpeed = 20;
                            missles[j].velocityX = missleSpeed*Math.sin(-missles[j].rotateAngle);
                            missles[j].velocityY = missleSpeed*Math.cos(-missles[j].rotateAngle);
                            missles[j].visible = true;
                            break;
                        }
                    }
                }
            }
        ]
    
        W.starBehavior = [
            {execute:function(sprite,time){
                if(sprite.top > canvas.height){
                    sprite.left = Math.random()*canvas.width;
                    sprite.top = Math.random()*canvas.height - canvas.height;
                }
                sprite.top += sprite.speed;
            }}
        ]
    
        W.starPainter = {
            paint:function(sprite){
                ctx.drawImage(sprite.cacheCanvas , sprite.left-sprite.width/2-sprite.lightLength , sprite.top-sprite.width/2-sprite.lightLength)
            },
    
            cache:function(sprite){
                sprite.cacheCtx.save();
                var opacity = 0.5,addopa = 1/sprite.lightLength;
                sprite.cacheCtx.fillStyle = "rgba(255,255,255,0.8)";
                sprite.cacheCtx.beginPath();
                sprite.cacheCtx.arc(sprite.width/2+sprite.lightLength , sprite.width/2+sprite.lightLength , sprite.width/2 , 0 , 2*Math.PI);
                sprite.cacheCtx.fill();
                for(var i=1;i<=sprite.lightLength;i+=2){
                    opacity-=addopa;
                    sprite.cacheCtx.fillStyle = "rgba(255,255,255,"+opacity+")";
                    sprite.cacheCtx.beginPath();
                    sprite.cacheCtx.arc(sprite.width/2+sprite.lightLength , sprite.width/2+sprite.lightLength , sprite.width/2+i , 0 , 2*Math.PI);
                    sprite.cacheCtx.fill();
                }
            }
        }
    
        W.foodBehavior = [
            {execute:function(sprite,time){
                sprite.top += sprite.speed;
                if(sprite.top > canvas.height+sprite.width){
                    sprite.visible = false;
                }
            }}
        ]
    
        W.foodPainter = {
            paint:function(sprite){
                ctx.fillStyle = "rgba("+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+","+parseInt(Math.random()*255)+",1)"
                ctx.font="15px 微软雅黑"
                ctx.textAlign = "center";
                ctx.textBaseline = "middle";
                ctx.fillText(sprite.kind , sprite.left , sprite.top);
            }
        }
    
    
    
        W.missleBehavior = [{
            execute:function(sprite,time){
                sprite.left -= sprite.velocityX;
                sprite.top -= sprite.velocityY;
                if(sprite.left<-missleWidth/2||sprite.top<-missleHeight/2||sprite.left>canvas.width+missleWidth/2||sprite.top<-missleHeight/2){
                    sprite.visible = false;
                }
            }
        }];
    
        W.misslePainter = {
            paint:function(sprite){
                var img = new Image();
                img.src="../planGame/image/plasma.png"
                ctx.drawImage(img , -missleWidth/2+1 , -missleHeight/2+1 , missleWidth , missleHeight);
            }
        }
    
        W.badPlanBehavior = [{
            execute:function(sprite,time){
                if(sprite.top > canvas.height || !sprite.visible){
                    var random = Math.random();
    
                    if(point>=200&&point<400){
                        sprite.fullBlood = 150;
                        if(random<0.1){
                            sprite.badKind = 2;
                            sprite.fullBlood = 250;
                        }
                    }else if(point>=400&&point<600){
                        sprite.fullBlood = 250;
                        if(random<0.2){
                            sprite.badKind = 2;
                            sprite.fullBlood = 400;
                        }
                        if(random<0.1){
                            sprite.badKind = 3;
                            sprite.fullBlood = 600;
                        }
                    }else if(point>=600){
                        sprite.fullBlood = 500;
                        if(random<0.4){
                            sprite.badKind = 2;
                            sprite.fullBlood = 700;
                        }
                        if(random<0.2){
                            sprite.badKind = 3;
                            sprite.fullBlood = 1000;
                        }
                    }
    
                    sprite.visible = true;
                    sprite.blood = sprite.fullBlood;
                    sprite.left = Math.random()*(canvas.width-2*planWidth)+planWidth;
                    sprite.top = Math.random()*canvas.height - canvas.height;
                }
                sprite.top += sprite.speed;
            },
            shot:function(sprite){
                this.addMissle(sprite , sprite.rotateAngle);
                var missleAngle = 0.1
                for(var i=1;i<sprite.fireLevel;i++){
                    this.addMissle(sprite , sprite.rotateAngle-i*missleAngle);
                    this.addMissle(sprite , sprite.rotateAngle+i*missleAngle);
                }
            },
            addMissle:function(sprite , angle){
                for(var j=0;j<missles.length;j++){
                    if(!missles[j].visible){
                        missles[j].left = sprite.left;
                        missles[j].top = sprite.top;
                        missles[j].rotateAngle = angle;
                        var missleSpeed = 20;
                        missles[j].velocityX = missleSpeed*Math.sin(-missles[j].rotateAngle);
                        missles[j].velocityY = missleSpeed*Math.cos(-missles[j].rotateAngle);
                        missles[j].visible = true;
                        break;
                    }
                }
            }
        }];
    
        W.badPlanPainter = {
            paint:function(sprite){
                var img = new Image();
                img.src="../planGame/image/ship.png"
                switch(sprite.badKind){
                    case 1:ctx.drawImage(img , 96 , 0 , planWidth , planWidth , -planWidth/2 , -planHeight/2 , planWidth , planWidth);
                    break;
    
                    case 2:ctx.drawImage(img , 120 , 0 , planWidth , planWidth , -planWidth/2 , -planHeight/2 , planWidth , planWidth);
                    break;
    
                    case 3:ctx.drawImage(img , 144 , 0 , planWidth , planWidth , -planWidth/2 , -planHeight/2 , planWidth , planWidth);
                    break;
                }
    
                ctx.strokeStyle = "#FFF";
                ctx.fillStyle = "#F00";
                var bloodHeight = 1;
                ctx.strokeRect(-planWidth/2-1 , planHeight+bloodHeight+3 , planWidth+2 , bloodHeight+2);
                ctx.fillRect(planWidth/2-planWidth*sprite.blood/sprite.fullBlood , planHeight+bloodHeight+3 , planWidth*sprite.blood/sprite.fullBlood , bloodHeight);
            }
        }
    
        W.planSize = function(){
            return {
                w:planWidth,
                h:planHeight
            }    
        }
    })(window);
    View Code

    这些绘制方法之类的都相对比较简单。

      主要说一下飞机的运动以及对象数量的控制,飞机怎么运动?毫无疑问,通过键盘控制它运动,可能很多人就会想到通过keydown这个方法按下的时候通过判断keyCode来让飞机持续运动。但是有个问题,keydown事件不支持多键按下,也就是说,当你按下X键时,keyCode是88,与此同时你按下方向键后,keyCode会瞬间变成37,也就是说,如果你单纯的想靠keydown来控制飞机运动,飞机就只能做一件事,要么只可以往某个方向移动,要么只会开枪。

      所以,我们要通过keydown和keyup来实现飞机的运动,原理很容易理解:当我们按下往左的方向键时,我们给飞机一个往左的状态,也就是让飞机的toLeft属性为true,而在动画循环中,判断飞机的状态,如果toLeft为true则飞机的x值不停地减少,飞机也就会不停地往左移动,然后当我们抬起手指时触发keyup事件,我们就再keyup事件中解除飞机往左的状态。飞机也就停止往左移动了。其他状态也一样的原理,这样写的话,就能够让飞机多种状态于一生了。可以同时开枪同时到处跑了。

    实现的代码如下:

    //keydown/keyup事件的绑定  
      window.onkeydown = function(event){
                switch(event.keyCode){
                    case 88:myplan.fire = true;
                    break;
                    case 90:myplan.rotateLeft=true;
                    break;
                    case 67:myplan.rotateRight=true;
                    break;
                    case 37:myplan.toLeft = true;
                    break;
                    case 38:myplan.toTop = true;
                    break;
                    case 39:myplan.toRight = true;
                    break;
                    case 40:myplan.toBottom = true;
                    break;
                }
            }
    
            window.onkeyup = function(event){
                switch(event.keyCode){
                    case 88:myplan.fire = false;
                    break;
                    case 90:myplan.rotateLeft=false;
                    break;
                    case 67:myplan.rotateRight=false;
                    break;
                    case 37:myplan.toLeft = false;
                    break;
                    case 38:myplan.toTop = false;
                    break;
                    case 39:myplan.toRight = false;
                    break;
                    case 40:myplan.toBottom = false;
                    break;
                }
            }    
    
    
    //飞机每一帧的状态更新处理代码
    execute:function(sprite,time){
                if(sprite.toTop){
                    sprite.top = sprite.top<planHeight/2? sprite.top : sprite.top-sprite.velocityY;
                }
                if(sprite.toLeft){
                    sprite.left = sprite.left<planWidth/2? sprite.left : sprite.left-sprite.velocityX;
                }
                if(sprite.toRight){
                    sprite.left = sprite.left>canvas.width-planWidth/2? sprite.left : sprite.left+sprite.velocityX;
                }
                if(sprite.toBottom){
                    sprite.top = sprite.top>canvas.height-planHeight/2? sprite.top : sprite.top+sprite.velocityY;
                }
                if(sprite.rotateLeft){
                    sprite.rotateAngle -= sprite.rotateSpeed;
                }
                if(sprite.rotateRight){
                    sprite.rotateAngle += sprite.rotateSpeed;
                }
                if(sprite.fire&&!sprite.painter.isActive){
                    sprite.painter.isActive = true;
                    this.shot(sprite);
    
                }

    就是如此简单。

      然后说下对象控制,打飞机游戏,会发射大量子弹,产生大量对象,包括爆炸啊,飞机啊,子弹等,如果不停地进行对象的生成和销毁,会让浏览器的负荷变得很大,运行了一段时间后就会卡出翔了。所以,我们要用可以循环利用的对象来解决这个问题,不进行对象的销毁,对所有对象进行保存,循环利用。

      我的做法就是,在游戏初始化的时候,直接生成一定数量的对象,存放在数组里面。当我们需要一个对象的时候,就从里面取,当用完后,再放回数组里面。数组里的所有对象都有一个属性,visible,代表对象当前是否可用。

      举个例子,当我的飞机发射一发炮弹,我需要一发炮弹,所以我就到炮弹数组里遍历,如果遍历到的炮弹visible为true,也就说明该对象正在使用着,不能拿来用,所以继续遍历,直到遍历到visible为false的炮弹对象,说明这个对象暂时没人用。然后就可以拿过来重新设置属性,投入使用了。当炮弹击中敌人或者打出画布外的时候,把炮弹的visible设成false,又成了一个没人用的炮弹在数组里存放起来等待下一次调用。

      所以,我们要预算算好页面大概要用到多少个对象,然后就预先准备好对象,这样,在游戏进行中,不会有对象进行生成和销毁,对游戏性能方面就有了提升了。

      

      最后再说下音频,游戏里面要用到多个同样的audio才能保证音效的不间断性:

    var audio = document.getElementsByTagName("audio");
                                                for(var i=0;i<audio.length;i++){
                                                    console.log(audio[i].paused)
                                                    if(audio[i].src.indexOf("boom")>=0&&audio[i].paused){
                                                        audio[i].play();
                                                        break;
                                                    }
                                                }

     

    好吧,基本上就这样了。技术或许还不够好,纯碎做个记录,如果代码有不当正处,欢迎指出,共同学习。

    源码地址:https://github.com/whxaxes/canvas-test/tree/gh-pages/src/Game-demo/planGame

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  • 原文地址:https://www.cnblogs.com/axes/p/3582843.html
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