Asp.net web api 如何将文件上载到服务器？

这是我的api

[HttpPost]        
[Route("uploadfile")]

    public HttpResponseMessage PostFile(HttpRequest request)
    {
        HttpResponseMessage result = null;
        var httpRequest = request;//HttpContext.Current.Request;
        if (httpRequest.Files.Count > 0)
        {
            var docfiles = new List<string>();
            foreach (string file in httpRequest.Files)
            {
                var postedFile = httpRequest.Files[file];
                var filePath = HttpContext.Current.Server.MapPath("Uploads/" + postedFile.FileName);
                postedFile.SaveAs(filePath);

                docfiles.Add(filePath);
            }
            result = Request.CreateResponse(HttpStatusCode.Created, docfiles);
        }
        else
        {
            result = Request.CreateResponse(HttpStatusCode.BadRequest);
        }
        return result;
    }

我犯了个错误{ “消息”：“此资源不支持请求实体的媒体类型‘多部分/表单数据’。”， “exceptionMessage”：“没有MediaTypeFormatter可用于从媒体类型为“multipart/form data”的内容中读取类型为“HttpRequest”的对象。”， “exceptionType”：“System.Net.Http.UnsupportedMediaTypeException”， “stackTrace”：“在System.Net.Http.HttpContentExtensions.ReadAsAsync[T]（HttpContent内容，类型，IEnumerable

1格式化程序，IFormatterLogger格式化程序记录器，CancellationToken CancellationToken）位于System.Net.Http.HttpContentExtensions.ReadAsAsync位于System.Web.Http.ModelBinding.FormatterParameterBinding.ReadContentAsync的（HttpRequestMessage请求，类型，IEnumerable

1格式化程序，IFormatterLogger格式化程序记录器，CancellationToken CancellationToken）

---

}

您还没有问过任何问题。会发生什么？您希望发生什么？您同时上载三件事是有原因的吗？我想将一个文件从客户端上载到服务器。那么，为什么要上载字符串、文件流和字节数组呢？试着一次只做一件事……它的文件名、文件和文件大小是否存在任何问题上传文件的方法？

  private async void button_Click(object sender, RoutedEventArgs e)
   {
   byte[] a = File.ReadAllBytes(@"C:\My folder\MyFile.txt");
        FileStream stream = File.Open(@"C:\My folder\MyFile.txt", FileMode.Open);

        Upload(@"http://localhost:56885/uploadfile", "MyFile", stream, a);

        MessageBox.Show("File uploaded Successfully");
   }

   private Stream Upload(string url, string param1, 
   Stream fileStream, byte[] fileBytes)        
   {
        HttpContent stringContent = new StringContent(param1);
        HttpContent fileStreamContent = new StreamContent(fileStream);
        HttpContent bytesContent = new ByteArrayContent(fileBytes);
        using (var client = new HttpClient())
        using (var formData = new MultipartFormDataContent())
        {
            formData.Add(stringContent, "param1", "param1");
            formData.Add(fileStreamContent, "file1", "file1");
            formData.Add(bytesContent, "file2", "file2");

            var response = client.PostAsync(url, formData).Result;

            if (!response.IsSuccessStatusCode)
            {
                return null;

            }

            MessageBox.Show("File uploaded Successfully");
            return response.Content.ReadAsStreamAsync().Result;
        }

    }