Sound 音乐工具类【转载】

package 
{
    import flash.events.Event;
    import flash.events.EventDispatcher;
    import flash.media.Sound;
    import flash.media.SoundChannel;
    import flash.media.SoundMixer;
    import flash.media.SoundTransform;
    import flash.net.URLLoader;
    import flash.net.URLRequest;
    import flash.utils.Dictionary;
    
    /*
    *使用方法：一般是直接在文档类初始化一个静态对象，比如定义为Main.soundManager
    *添加一个声音：Main.soundManager.addSound(声音id,声音url地址);//通过id访问管理器中的声音
    *添加并播放一个声音：Main.soundManager.addAndPlaySound(声音id,声音url地址,循环次数);//如果需要一直播放背景音，建议把循环次数设置为int.MAX_VALUE
    *播放指定声音：Main.soundManager.play(声音id,循环次数);//默认为播放一次
    *停止指定声音：Main.soundManager.stop(声音id);
    *获得指定声音的Sound对象：Main.soundManager.getSound(声音id);
    *获得指定声音的SoundChannel对象：Main.soundManager.getSoundChannel(声音id);
    *移除指定声音：Main.soundManager.removeSound(声音id);
    *设置音量大小：Main.soundManager.setVolume(声音大小);//0静音~1最大
    *停止播放所有声音：Main.soundManager.stopAllSound();
    */


    public class SoundManager extends EventDispatcher
    {
        private var soundDic:Dictionary;
        private var soundChannelDic:Dictionary;
        private var urlLoader:URLLoader;
        
        public function SoundManager()
        {
            super();
            init();
        }
        private function init():void
        {
            soundDic = new Dictionary  ;
            soundChannelDic = new Dictionary  ;
            urlLoader = new URLLoader  ;
        }
        public function addSound(id:String,url:String):void
        {
            if (soundDic[id])
            {
                return;
            }
            var sound:Sound = new Sound  ;
            sound.addEventListener(Event.COMPLETE,addComplete);
            sound.load(new URLRequest(url));
            function addComplete(e:Event):void
            {
                sound.removeEventListener(Event.COMPLETE,addComplete);
                soundDic[id] = sound;
            }
        }
        public function addAndPlaySound(id:String,url:String,loops:int=0):void
        {
            if (soundDic[id])
            {
                /**如果已经有这个音乐 那么就直接播放不添加**/
                soundDic[id].play();
                return;
            }
            var sound:Sound = new Sound  ;
            sound.addEventListener(Event.COMPLETE,addAndPlayComplete);
            sound.load(new URLRequest(url));
            function addAndPlayComplete(e:Event):void
            {
                sound.removeEventListener(Event.COMPLETE,addAndPlayComplete);
                soundDic[id] = sound;
                var soundChannel:SoundChannel = sound.play(0,loops);
                soundChannelDic[id] = soundChannel;
            }
        }
        public function play(id:String,loops:int=0):void
        {
            if (soundDic[id])
            {
                if (soundChannelDic[id])                
                {                    
                    soundChannelDic[id].stop();       
                    soundChannelDic[id] = soundDic[id].play(0, loops);    
                }               
                else       
                {           
                    soundChannelDic[id] = soundDic[id].play(0, loops);   
                } 
            }
        }
        public function stop(id:String):void
        {
            if (soundChannelDic[id])
            {
                soundChannelDic[id].stop();
            }
        }
        public function getSound(id:String):Sound
        {
            if (soundDic[id])
            {
                return soundDic[id];
            }
            return null;
        }
        public function getSoundChannel(id:String):SoundChannel
        {
            if (soundChannelDic[id])
            {
                return soundChannelDic[id];
            }
            return null;
        }
        public function removeSound(id:String):void
        {
            if (soundDic[id])
            {
                if (soundChannelDic[id])
                {
                    soundChannelDic[id].stop();
                    soundChannelDic[id] = null;
                    delete soundChannelDic[id];
                }
                soundDic[id] = null;
                delete soundDic[id];
            }
        }
        public function setVolume(value:Number):void
        {
            SoundMixer.soundTransform = new SoundTransform(value);
        }
        public function stopAllSound():void
        {
            SoundMixer.stopAll();
        }
    }
}