来自.NET CF 3.5的AWS IoT POST请求

Question

我遇到以下问题 - 我尝试从具有.NET CF 3.5的设备向AWS IoT执行POST请求，以将消息发布到主题。它适用于对Azure IoT Hub和.NET 4.5上的应用程序执行相同操作。但是当我尝试向AWS发出请求时，我总是得到异常the connection has timed out。 这就是我执行请求的方式：

    public static HttpWebResponse InvokeHttpRequest(Uri endpointUri,
                                         string httpMethod,
                                         IDictionary<string, string> headers,
                                         string requestBody)
    {
        try
        {
            var request = ConstructWebRequest(endpointUri, httpMethod, headers);

            if (!string.IsNullOrEmpty(requestBody))
            {
                var buffer = new byte[requestBody.Length]; // arbitrary buffer size                        
                var requestStream = request.GetRequestStream();
                using (var inputStream = new MemoryStream(Encoding.UTF8.GetBytes(requestBody)))
                {
                    var bytesRead = 0;
                    while ((bytesRead = inputStream.Read(buffer, 0, buffer.Length)) > 0)
                    {
                        requestStream.Write(buffer, 0, bytesRead);
                    }
                }
                requestStream.Flush();
                requestStream.Close();
            }

            return CheckResponse(request);
        }
        catch (WebException ex)
        {
            using (var response = ex.Response as HttpWebResponse)
            {
                if (response != null)
                {
                    var errorMsg = ReadResponseBody(response);
                    Console.WriteLine("\n-- HTTP call failed with exception '{0}', status code '{1}'", errorMsg, response.StatusCode);
                }
                return null;
            }
        }
    }

网址，标题和其他所有内容都可以，因为它适用于.NET 4.5。是否存在可能导致此类问题的CF的已知限制？

注意 我需要添加

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

在.NET 4.5客户端中，因为否则我得到了异常The server committed a protocol violation. Section=ResponseStatusLine，所以这个信息可能有所帮助。谢谢！

UPD 以下是ConstructWebRequest和CheckResponse代码：

public static HttpWebRequest ConstructWebRequest(Uri endpointUri,
    string httpMethod,
    IDictionary<string, string> headers)
{
    var request = (HttpWebRequest)WebRequest.Create(endpointUri);
    request.Method = httpMethod;

    foreach (var header in headers.Keys)
    {
        // not all headers can be set via the dictionary
        if (header.Equals("host", StringComparison.OrdinalIgnoreCase))
            continue;
        else if (header.Equals("content-length", StringComparison.OrdinalIgnoreCase))
            request.ContentLength = long.Parse(headers[header]);
        else if (header.Equals("content-type", StringComparison.OrdinalIgnoreCase))
            request.ContentType = headers[header];
        else
            request.Headers.Add(header, headers[header]);
    }
    return request;
}

public static void CheckResponse(HttpWebRequest request)
{
    // Get the response and read any body into a string, then display.
    using (var response = (HttpWebResponse)request.GetResponse())
    {
        if (response.StatusCode == HttpStatusCode.OK)
        {
            Console.WriteLine("\n-- HTTP call succeeded");
            var responseBody = ReadResponseBody(response);
            if (!string.IsNullOrEmpty(responseBody))
            {
                Console.WriteLine("\n-- Response body:");
                Console.WriteLine(responseBody);                        
            }
        }
        else
            Console.WriteLine("\n-- HTTP call failed, status code: {0}", response.StatusCode);
    }
}