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我尝试使用 PushStreamContent 和 WebApi 流式传输音频。为此，我编写了一些代码。主要代码；

[HttpGet]
public HttpResponseMessage StreamCall(long callId,int playSpeed)
{
    var audio = new AudioStreamHelper();

    var response = Request.CreateResponse();
    response.Content = new PushStreamContent((Action<Stream, HttpContent, TransportContext>) audio.WriteToStream, new MediaTypeHeaderValue("audio/wav"));

    return response;
}

AudioStreamHelper 代码；

public class AudioStreamHelper
{
    private readonly string _filename;
    protected static readonly ILogger Logger = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType.Name);
    public AudioStreamHelper()
    {
        _filename = @"C:/195545.mp3";
    }
    public async void WriteToStream(Stream outputStream, HttpContent content, TransportContext context)
    {
        try
        {
            var buffer = new byte[12365536];

            using (var audio = File.Open(_filename, FileMode.Open, FileAccess.Read,FileShare.ReadWrite))
            {
                var length = (int)audio.Length;
                var bytesRead = 1;

                while (length > 0 && bytesRead > 0)
                {
                    bytesRead = audio.Read(buffer, 0, Math.Min(length, buffer.Length));
                    await outputStream.WriteAsync(buffer, 0, bytesRead);
                    length -= bytesRead;
                }
            }
        }
        catch (HttpException ex)
        {
            Logger.Error(ex.Message);
            throw new UserFriendlyException(AppTexts.AudioStreamError);
        }
        finally
        {
            outputStream.Close();
        }
    }
}

当我调试这段代码时；在 AudioStreamHelper 类 WriteToStream 方法和await outputStream.WriteAsync(buffer, 0, bytesRead);行中，我的线程被锁定/冻结并且没有响应。我检查当前线程 ID。是一样的。（在 Api 和 Helper 类中）此外，此代码适用于 System.Net.Http.Formattion（版本 4.0.0.0）的另一个演示应用程序我的项目使用 System.Net.Http.Formattion（版本 5.1.0.0）关联有这个条件？我不明白这种情况。

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0 回答 0