model-view-controller - 出现错误：HttpRequestException：收到无效的标头名称：'Content=Transfer-Encoding'。使用 MVC Core 下载文件时

Question

我正在尝试让 MVC 核心（3.1）中的控制器下载音频文件以呈现给用户，但我尝试的一切都以错误告终：

HttpRequestException: Received an invalid header name: 'Content=Transfer-Encoding'.

我试过 webclient、httpclient 和最近的 webrequest/webresponse。我的代码现在看起来像这样（为安全起见删除了细节）：

WebRequest downloadRequest = WebRequest.Create({url here});
            downloadRequest.Headers.Add("Cookie", "{cookie data here};");
            downloadRequest.Headers.Add("Accept", "application/json, text/javascript, */*; q=0.01");
            downloadRequest.Headers.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:73.0) Gecko/20100101 Firefox/73.0");
            downloadRequest.Headers.Add("Sec-Fetch-Dest", "empty");
            downloadRequest.Headers.Add("X-Requested-With", "XMLHttpRequest");

            using (WebResponse webResponse = await downloadRequest.GetResponseAsync())
            {

                 return File(webResponse.GetResponseStream(), "audio/wav", wavFile + ".txt");
            }

错误在线

 using (WebResponse webResponse = await downloadRequest.GetResponseAsync())

使用提琴手，请求看起来不错，它抱怨的标头是：Content=Transfer-Encoding: binary，它在 content-disposition 中有文件作为附件。不幸的是，我完全无法控制发送服务器，但这在浏览器中运行良好。谁能告诉我我做错了什么？

谢谢

标签： model-view-controller.net-corewebclient

Answer 1

传入的请求看起来格式不正确。Transfer-Encoding 是它自己的标头名称。您不能将其分配给另一个标头的值。而且 AFAIK，内容甚至不是标准的 HTTP 标头名称。

有关有效的 Content-* 标头，请参阅https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers#Message_body_information中的列表。Transfer-Encoding 标头记录在https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Transfer-Encoding。

编辑框架 4.8 及以下

我必须将以下行添加到 app.config 以让客户端处理来自服务器的无效响应。

<system.net>
  <settings>
    <httpWebRequest useUnsafeHeaderParsing="true" />
  </settings>
</system.net>

程序本身如下所示。

try
{
    var httpclient = new HttpClient();
    var response = await httpclient.GetAsync("http://localhost:9091");

    var attachment = new byte[1024];
    foreach (var h in response.Content.Headers)
    {
        var e = h.Value.GetEnumerator();
        e.MoveNext();
        attachment = Encoding.UTF8.GetBytes(e.Current); // Convert UTF-8 encoded string into raw bytes

        Console.WriteLine($"{h.Key}, {Encoding.UTF8.GetString(attachment)}"); // Save raw bytes to disk instead of converting back to string and writing to Console
    }
}
catch (Exception exception)
{
    Console.WriteLine(exception.Message);
}

编辑 dotnet 核心

try
{
    var s = new Socket(SocketType.Stream, ProtocolType.Tcp);
    var a = IPAddress.Parse("127.0.0.1");
    await s.ConnectAsync(a, 9091);

    var request = "GET http://localhost:9091/";
    var outBytes = Encoding.UTF8.GetBytes(request);
    var outBuffer = new ArraySegment<byte>(outBytes);

    await s.SendAsync(outBuffer, SocketFlags.None);

    var inBytes = new byte[1024];
    var inBuffer = new ArraySegment<byte>(inBytes);
    await s.ReceiveAsync(inBuffer, SocketFlags.None);

    var r = Encoding.UTF8.GetString(inBuffer.Array);
}
catch (SocketException exception)
{
    Console.WriteLine($"Error: {exception.Message}");
}