C# Owin自主机不一致中的多部分Web API操作

我有一个自托管的owin web api应用程序，它有一个操作，将多部分/表单数据保存到服务器中的内容目录中（稍后将以http链接的形式发送到用户的图像文件，这是一个好方法吗？）。以下是控制器代码：

        [HttpPost]
    public async Task<object> Post()
    {
        if (!Request.Content.IsMimeMultipartContent("form-data"))
        {
            throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.UnsupportedMediaType));
        }

        string rootFolder = Path.Combine("Content");
        var provider = new NamedMultipartFormDataStreamProvider(rootFolder);

        try
        {
            //read the form data
            await Request.Content.ReadAsMultipartAsync(provider);

            foreach (MultipartFileData file in provider.FileData)
            {
                Trace.WriteLine(file.Headers.ContentDisposition.FileName);
                Trace.WriteLine("Saving to server... " + file.LocalFileName);

            }

            return Request.CreateResponse(HttpStatusCode.OK);
        }
        catch (System.Exception e)
        {
            return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, e);
        }

    }

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

Mono JIT编译器版本3.8.0中失败的POST

Remote Address:127.0.0.1:2004
Request URL:http://localhost:2004/api/stories
Request Method:POST
Status Code:415 Unsupported Media Type
Request Headersview source
Accept:text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
Accept-Encoding:gzip,deflate
Accept-Language:en-US,en;q=0.8
Cache-Control:max-age=0
Connection:keep-alive
Content-Length:681954
Content-Type:multipart/form-data; boundary=----WebKitFormBoundaryW4NqTv782jlZ186F
Host:localhost:2004
Origin:http://localhost:2004
Referer:http://localhost:2004/api/help
User-Agent:Mozilla/5.0 (Macintosh; Intel Mac OS X 10_9_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/37.0.2062.94 Safari/537.36
Request Payload
------WebKitFormBoundaryW4NqTv782jlZ186F
Content-Disposition: form-data; name="caption"

This is Test Image Caption
------WebKitFormBoundaryW4NqTv782jlZ186F
Content-Disposition: form-data; name="image1"; filename="1407231597673.png"
Content-Type: image/png


------WebKitFormBoundaryW4NqTv782jlZ186F--
Response Headersview source
Content-Length:0
Date:Mon, 08 Sep 2014 23:39:11 GMT
Keep-Alive:timeout=15,max=100
Server:Mono-HTTPAPI/1.0

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

我该如何解决这个问题

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

问候

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

编辑

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

如果我对ISIMEMultipartContent（“表单数据”）部分进行注释，它会给出follow错误

ExceptionMessage: "Invalid 'HttpContent' instance provided.
It does not have a  content-type header value.
'HttpContent' instances must have a content-type header starting with 'multipart/'. Parameter name: content",
ExceptionType: "System.ArgumentException",

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

如果有人想知道是否使用了

NamedMultipartFormDataStreamProvider

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

编辑2：

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

似乎是Mono bug，它包含在下面的if中

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

这可能是Mono错误，其中if Request.Content.Headers.ContentType从未初始化，并且始终为null。通过调试时，同时在Windows中正确初始化Request.Content.Headers.ContentType，但在Mono中从未正确初始化

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }

  if (Request.Content.Headers.ContentType == null)
        {
            Console.WriteLine("header is null");
        }