如何使用临时文件流式传输mp3文件？

我正在使用Mp3流光。 要从url流式传输mp3文件，我想使用临时文件。 但是尝试读取和写入相同的文件会因File.ReadAllBytes而抛出IOException ，因为该文件正在使用中。 我怎样才能解决这个问题？

 long pos = 0; string path = pathtothetempfile; MemoryStream ms = new MemoryStream(); FileStream fs = new FileStream(path, FileMode.Create, FileAccess.ReadWrite, FileShare.ReadWrite); do { bytesRead = responseStream.Read(buffer, 0, buffer.Length); fs.Write(buffer, 0, bytesRead); fs.Flush(); byte[] tempBuffer = File.ReadAllBytes(path); pos = ms.Position; ms = new MemoryStream(tempBuffer); ms.Position = pos; frame = Mp3Frame.LoadFromStream(ms); //....codes.... } while(bytesRead > 0) 

Answer 1

我通过搜索得到了自己的答案。 这个答案包含控制Mp3的NAudio，它通过部分读取流来实现RAM友好。 我正在为有同样问题的其他人分享它。

  WaveOut waveOut; AcmMp3FrameDecompressor decompressor; BufferedWaveProvider provider; bool firstPlay = true; public void Play() { Task.Run(() => { #region WebRequest creator HttpWebResponse response = null; if (avgbytes < 0) { HttpWebRequest req = WebRequest.Create(url) as HttpWebRequest; req.AllowAutoRedirect = true; req.UserAgent = "Mozilla/5.0 (Windows NT 6.3; WOW64; rv:31.0) Gecko/20100101 Firefox/31.0"; response = req.GetResponse() as HttpWebResponse; contentLength = response.ContentLength; } else response = Helper.CreateAudioWebRequest(url, currentTime, avgbytes) .GetResponse() as HttpWebResponse; Stream responseStream = response.GetResponseStream(); #endregion #region Local Variables byte[] buffer = new byte[17 * 1024]; byte[] bigBuffer = new byte[response.ContentLength]; int bytesRead = 0; long pos = 0; long postotal = 0; string path = System.IO.Path.GetTempPath() + Guid.NewGuid().ToString() + ".mp3"; #endregion Mp3Frame frame; FileStream fs = new FileStream(path, FileMode.Create, FileAccess.ReadWrite, FileShare.ReadWrite); do { bytesRead = responseStream.Read(buffer, 0, buffer.Length); fs.Write(buffer, 0, bytesRead); fs.Flush(); using (MemoryStream ms = new MemoryStream(ReadPartial(fs, postotal, 1024 * 10))) { ms.Position = 0; frame = Mp3Frame.LoadFromStream(ms); if (frame == null) { continue; } pos = ms.Position; postotal += pos; } #region First Play if (firstPlay) { avgbytes = new Mp3WaveFormat(frame.SampleRate, frame.ChannelMode == ChannelMode.Mono ? 1 : 2, frame.FrameLength, frame.BitRate).AverageBytesPerSecond; duration = (int)(response.ContentLength * 1d / avgbytes); firstPlay = false; } #endregion #region Decompress Frame if (decompressor == null) { decompressor = CreateFrameDecompressor(frame) as AcmMp3FrameDecompressor; provider = new BufferedWaveProvider(decompressor.OutputFormat); provider.BufferDuration = TimeSpan.FromSeconds(20); } int decompressed = decompressor.DecompressFrame(frame, buffer, 0); #endregion #region BufferedWaveProvider Area if (IsBufferNearlyFull(provider)) { Thread.Sleep(500); } provider.AddSamples(buffer, 0, decompressed); #endregion if (provider.BufferedDuration.TotalSeconds >= 2 && waveOut == null) { waveOut = new WaveOut(); waveOut.Init(provider); waveOut.Play(); } } while (postotal != contentLength || bytesRead > 0 || waveOut==null || (waveOut != null && waveOut.PlaybackState == PlaybackState.Playing)); }); } public static byte[] ReadStreamPartially(System.IO.Stream stream, long offset, long count) { long originalPosition = 0; if (stream.CanSeek) { originalPosition = stream.Position; stream.Position = offset; } try { byte[] readBuffer = new byte[4096]; byte[] total = new byte[count]; int totalBytesRead = 0; int byteRead; while ((byteRead = stream.ReadByte()) != -1) { Buffer.SetByte(total, totalBytesRead, (byte)byteRead); totalBytesRead++; if (totalBytesRead == count) { stream.Position = originalPosition; break; } } if (totalBytesRead < count) { byte[] temp = new byte[totalBytesRead]; Buffer.BlockCopy(total, 0, temp, 0, totalBytesRead); stream.Position = originalPosition; return temp; } return total; } finally { if (stream.CanSeek) { stream.Position = originalPosition; } } } private bool IsBufferNearlyFull(BufferedWaveProvider bufferedWaveProvider) { return bufferedWaveProvider != null && bufferedWaveProvider.BufferLength - bufferedWaveProvider.BufferedBytes < bufferedWaveProvider.WaveFormat.AverageBytesPerSecond / 4; } private static IMp3FrameDecompressor CreateFrameDecompressor(Mp3Frame frame) { WaveFormat waveFormat = new Mp3WaveFormat(frame.SampleRate, frame.ChannelMode == ChannelMode.Mono ? 1 : 2, frame.FrameLength, frame.BitRate); return new AcmMp3FrameDecompressor(waveFormat); }