flash 外部加载mp3 标准代码

package {
import flash.display.Sprite;
import flash.display.StageAlign;
import flash.display.StageScaleMode;
import flash.events.*;
import flash.media.Sound;
import flash.media.SoundChannel;
import flash.media.SoundTransform;
import flash.net.URLRequest;
import flash.utils.Timer;

public class SoundTransformExample extends Sprite {
private var url:String = "MySound.mp3";
private var soundFactory:Sound;
private var channel:SoundChannel;
private var positionTimer:Timer;

public function SoundTransformExample() {
stage.align = StageAlign.TOP_LEFT;
stage.scaleMode = StageScaleMode.NO_SCALE;

var request:URLRequest = new URLRequest(url);
soundFactory = new Sound();
soundFactory.addEventListener(IOErrorEvent.IO_ERROR, ioErrorHandler);
soundFactory.load(request);
channel = soundFactory.play();
stage.addEventListener(MouseEvent.MOUSE_MOVE, mouseMoveHandler);
}

private function ioErrorHandler(event:Event):void {
trace("ioErrorHandler: " + event);
}

private function setPan(pan:Number):void {
trace("setPan: " + pan.toFixed(2));
var transform:SoundTransform = channel.soundTransform;
transform.pan = pan;
channel.soundTransform = transform;
}

private function setVolume(volume:Number):void {
trace("setVolume: " + volume.toFixed(2));
var transform:SoundTransform = channel.soundTransform;
transform.volume = volume;
channel.soundTransform = transform;
}

private function mouseMoveHandler(event:MouseEvent):void {
var halfStage:uint = Math.floor(stage.stageWidth / 2);
var xPos:uint = event.stageX;
var yPos:uint = event.stageY;
var value:Number;
var pan:Number;

if (xPos > halfStage) {
value = xPos / halfStage;
pan = value - 1;
} else if (xPos < halfStage) {
value = (xPos - halfStage) / halfStage;
pan = value;
} else {
pan = 0;
}

var volume:Number = 1 - (yPos / stage.stageHeight);

setVolume(volume);
setPan(pan);

}
}
}