之前获取时长可以，但是有的音频文件就获取不到时长，时长是infinity，啥情况，是有路径的限制吗

// 获取当前音频时长

    that.innerAudioCtx.onCanplay(() => {

      console.log('oncanplay')

      that.innerAudioCtx.duration;

      setTimeout(() => {

        console.log(that.innerAudioCtx.duration)

        that.setData({

          curAudioTime:that.innerAudioCtx.duration,

        })

      }, 10);

    });