我还没有尝试过，但是这可能工作：

I haven't tried it but this might work:

如果您强制发送一个请求HTTP 1.0而不是HTTP 1.1，然后服务器将用
HTTP标头指定的Content-Length回复

If you forcefully send an request for Http 1.0 rather than Http 1.1 then server will reply with HTTP Header specifying Content-Length

HttpWebRequest wr = (HttpWebRequest)WebRequest.Create("http://localhost/audiotest/audio.wav");
wr.ProtocolVersion = Version.Parse("1.0"); 

HttpWebResponse response = (HttpWebResponse)request.GetResponse();

您将获得 response.GetResponseStream的文件流（）

所有信贷的这个