音频持续时间返回0.0

Question

我试图获取使用AVAudioRecorder（.m4a格式）录制的音频的持续时间，但以下代码打印出来＆＃34; 0.0＆＃34; ：

    let asset = AVURLAsset(URL: myAudioFileURL)
    let audioDuration = asset.duration
    print(Float(CMTimeGetSeconds(audioDuration)))

我做错了什么？ 感谢

Answer 1

do
    {
        let avAudioPlayer = try AVAudioPlayer (contentsOfURL:recordedAudioURL)
        duration = avAudioPlayer.duration
        let ms  = Int((duration%1)*1000)
        let sec = Int(duration%60)
        let minutes = Int(duration / 60) % 60
        let hours = Int(duration / 3600)
        recordedAudioDuration.text = (NSString(format: "Dur: %0.2d:%0.2d:%0.2d.%0.3d",hours,minutes,sec,ms)) as String
    }
    catch{
        print(error)
    }