1.必须要用 AVAudioSession，否则木有声音啊。
2.不要把 AVAudioPlayer 当做局部变量，要定义成全局变量
3.要找好路径，这里用 mainBundle，不要搞错。
private func playMusic() {
let musicPath = Bundle.main.path(forResource: "money", ofType: "mp3")
let fileUrl = NSURL.fileURL(withPath: musicPath ?? " ")
do {
let session = AVAudioSession.sharedInstance()
try session.setCategory(AVAudioSessionCategoryPlayback)
try session.setActive(true)
audioPlay = try AVAudioPlayer.init(contentsOf: fileUrl)
audioPlay.numberOfLoops = 0
audioPlay.volume = 0.5
audioPlay.currentTime = 0
audioPlay.prepareToPlay()
audioPlay.play()
}
catch {
debugLog(error)
}
}
