问从xamarin forms UWP应用程序将图像上传到asp.net核心应用程序接口时获得400响应

EN

 private async void UploadFile_Clicked(object sender, EventArgs e)
        {
            try
            {
                var url = "http://localhost:53416/api/upload";

                var content = new MultipartFormDataContent();

                content.Add(new StreamContent(_mediaFile.GetStream()),
                    "\"file\"",
                    $"\"{_mediaFile.Path}\"");

                var httpClient = new HttpClient();
                var httpResponseMessage = await httpClient.PostAsync(url, content);
            }
            catch (Exception ex)
            {
            }
        }

 [Route("api/Upload")]
        [HttpPost]
        public async Task<IActionResult> Post([FromForm(Name = "file")] IFormFile file)
        {
            try
            {
                var uploads = Path.Combine(webHostEnvironment.WebRootPath, "Uploads");
                if (file.Length > 0)
                {
                    using (var fileStream = new FileStream(Path.Combine(uploads, file.FileName), FileMode.Create))
                    {
                        await file.CopyToAsync(fileStream);
                    }
                }
                return Ok();
            }
            catch (Exception ex)
            {
                return StatusCode(500, $"Internal server error: {ex}");
            }
        }

 public async Task<IActionResult> Post()