Discord.net 无法使用 NAudio 传输音频

我想在语音频道中播放 mp3 文件。 BOT成功可以连接，但不播放任何内容，并抛出异常。

Code

public async Task SendAudioAsync(IGuild guild, IMessageChannel channel, string path)
{
    try
    {
        if (!File.Exists(path))
        {
            await channel.SendMessageAsync("File does not exist.");
            return;
        }
        IAudioClient client;
        if (ConnectedChannels.TryGetValue(guild.Id, out client))
        {
            await Log.d($"Starting playback of {path} in {guild.Name}", src);
            using (var reader = new Mp3FileReader(path))
            using (var output = client.CreateOpusStream())
            {
                try
                {
                    reader.CopyTo(output);//<- AudioService.cs, line: 70
                }
                catch(Exception e)
                {
                    await Log.e(e.ToString(), src);
                }
                finally { await output.FlushAsync(); }
            }
        }
    }
    catch (Exception e)
    {
        await Log.e(e.ToString(), src);
    }
}

例外

System.ArgumentException: Shift and length outside the array boundaries or the number of elements is greater than the number of items in the source collection from the index to the end of the collection. 
System.Buffer.BlockCopy(Array src, Int32 srcOffset , Array dst, Int32 dstOffset, Int32 count)
at Discord.Audio.Streams.BufferedWriteStream.<WriteAsync>d__21.MoveNext() 
--- Trigger end tracking from the previous occurrence of the exception --- 
at System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess (Task task)
at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
at Discord.Audio.AudioStream.Write(Byte [] buffer, Int32 offset, Int32 count)
at System.IO.Stream.InternalCopyTo(Stream destination, Int32 <SendAudioAsync> d__4.MoveNext() location: C:\Users\noel\source\repos\DiscordBot\Bot\Core\Voice\AudioService.cs, line: 70 

这个版本的例外，用谷歌翻译从匈牙利语翻译而来。

Update

我做了更多研究并发现这个例子，因为它已经过时了，我重写了一些，现在看起来像这样：

public async Task SendAudioAsync(IGuild guild, IMessageChannel channel, string path)
{
    try
    {
        if (!File.Exists(path))
        {
            await channel.SendMessageAsync("File does not exist.");
            return;
        }
        IAudioClient client;
        if (ConnectedChannels.TryGetValue(guild.Id, out client))
        {
            await Log.d($"Starting playback of \"{path}\" in \"{guild.Name}\"", src);
            var OutFormat = new WaveFormat(48000, 16, 2);

            using (var MP3Reader = new Mp3FileReader(path)) // Create a new Disposable MP3FileReader, to read audio from the filePath parameter
            using (var resampler = new MediaFoundationResampler(MP3Reader, OutFormat)) // Create a Disposable Resampler, which will convert the read MP3 data to PCM, using our Output Format
            {
                resampler.ResamplerQuality = 60; // Set the quality of the resampler to 60, the highest quality
                int blockSize = OutFormat.AverageBytesPerSecond / 50; // Establish the size of our AudioBuffer
                byte[] buffer = new byte[blockSize];
                int byteCount;
                while ((byteCount = resampler.Read(buffer, 0, blockSize)) > 0) // Read audio into our buffer, and keep a loop open while data is present
                {
                    if (byteCount < blockSize)
                    {
                        // Incomplete Frame
                        for (int i = byteCount; i < blockSize; i++)
                            buffer[i] = 0;
                    }
                    using(var output = client.CreatePCMStream(AudioApplication.Mixed))
                    await output.WriteAsync(buffer, 0, blockSize); // Send the buffer to Discord
                }
            }
        }
    }
    catch (Exception e)
    {
        await Log.e(e.ToString(), src);
    }
}

现在它不执行任何操作，也不会抛出任何异常。

我想出了这个代码，它对我有用。由于这被认为是一个测试程序，因此我并不真正关心同步/异步编程。适应这一点应该很容易。我希望这有帮助。

class Program
{
    private static string mytoken = "";
    private static CancellationTokenSource cancellationToken = new CancellationTokenSource();
    private static bool playing = false;
    private static AudioOutStream dstream = null;
    private static IAudioClient client = null;

    static void Main(string[] args)
    {
        var Client = new DiscordSocketClient();
        Client.LoginAsync(TokenType.Bot, mytoken).Wait();
        Client.StartAsync().Wait();

        var path = "path\\testfile.mp3";

        Client.Ready += async () =>
        {
            var guild = Client.Guilds.First();
            var channel = guild.Channels.Where(x => x is SocketVoiceChannel).Select(x => x as SocketVoiceChannel).First();

            try
            {
                client = await channel.ConnectAsync();

                var reader = new Mp3FileReader(path);
                var naudio = WaveFormatConversionStream.CreatePcmStream(reader);

                dstream = client.CreatePCMStream(AudioApplication.Music);
                byte[] buffer = new byte[naudio.Length];

                int rest = (int)(naudio.Length - naudio.Position);
                await naudio.ReadAsync(buffer, 0, rest);
                playing = true;
                await dstream.WriteAsync(buffer, 0, rest, cancellationToken.Token);
            }
            catch (Exception e)
            {
                Debug.WriteLine(e.Message);
                if(e.InnerException != null)
                    Debug.WriteLine(e.InnerException.Message);
            }

        };

        while (!playing) ;
        Console.ReadLine();
        cancellationToken.Cancel();
        Debug.WriteLine("Pre-Flush");
        dstream.Flush();
        Debug.WriteLine("POST-FLUSH");
        client.StopAsync().Wait();

        Client.StopAsync().Wait();
        Client.LogoutAsync().Wait();
    }
}

当不使用byte[]为了缓冲音频，我刚刚打电话naudio.CopyToAsync(dstream);