Http Post FormData - 发送文件导致formdata仅发布文件而忽略其他键

Question

我跟着这个：https://plnkr.co/edit/vokjd6?p=preview

并写下我的js：

$scope.AddFormData = new FormData();

$scope.AttachFile = function ($files) {
    //$scope.AddFormData.append('chk', 'test');
    angular.forEach($files, function (value, key) {
        $scope.AddFormData.append('file', value);
    });
    console.log($scope.AddFormData.entries());
}

$scope.saveStatus = function () {
    //FormData
    //var AddFormData = new FormData();

    //api/JobStatus/save
    $scope.AddFormData.append('dStatusDate', JSON.parse(angular.toJson($scope.uStatus.dStatusDate)));
    $scope.AddFormData.append('iJobId', JSON.parse(angular.toJson($scope.selJob)));
    $scope.AddFormData.append('iStatusId', angular.toJson($scope.uStatus.iStatusId));
    $scope.AddFormData.append('vDescription', JSON.parse(angular.toJson($scope.uStatus.vDescription)));
    //
    console.log($scope.AddFormData.entries());

    var request = {
        method: 'POST',
        url: '/api/save',
        data: $scope.AddFormData,
        headers: {
            'Content-Type': undefined
        },
        transformRequest: angular.identity
    }

    $http(request).then(function () {
        alert("Posted!");
        $scope.init();
    }, function () {
        alert("Error!");
    });
};

如果我不附带文件，它就能完美运行。但是当我添加文件时，我在我的.NET WebAPI中获取该文件，而其他密钥则不存在。在服务器端，FileData显示内容，FormData为空。

te POST处理程序的WebAPI代码位于：

    //POST: /api/save
    [HttpPost]
    [Route("api/save")]
    public IHttpActionResult PostFile()
    {
        HttpRequestMessage request = this.Request;
        if (!request.Content.IsMimeMultipartContent())
        {
            throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
        }
        ORG_jobs_status oRG_jobs_status = new ORG_jobs_status();
        string root = System.Web.HttpContext.Current.Server.MapPath("~/App_Data/jobstatus");
        var provider = new MultipartFormDataStreamProvider(root);
        Request.Content.ReadAsMultipartAsync(provider);
        try
        {
            oRG_jobs_status.iJobId = int.Parse(provider.FormData.GetValues("iJobId").FirstOrDefault());
            oRG_jobs_status.dStatusDate = DateTime.Parse(provider.FormData.GetValues("dStatusDate").FirstOrDefault());
            oRG_jobs_status.iStatusId = int.Parse(provider.FormData.GetValues("iStatusId").FirstOrDefault());
            oRG_jobs_status.vDescription = provider.FormData.GetValues("vDescription").FirstOrDefault();

            foreach (var file in provider.FileData)
            {
                oRG_jobs_status.vFileName = file.Headers.ContentDisposition.FileName.Trim('"');
                oRG_jobs_status.FileType = file.Headers.ContentType.ToString();
            }
            //What to store?
            //File name to be updated as
            //This will go outside
            //We save the data, get the autoid and then save the file.
            db.ORG_jobs_status.Add(oRG_jobs_status);
            db.SaveChanges();
            //In future, shall put it with a transaction!
            var serverFile = "jst_" + oRG_jobs_status.iJobStatusId.ToString() + "_" + oRG_jobs_status.vFileName;
            //File.Move(fileInfo.FullName, Path.Combine(root, guid + "_" + provider.FileData.First().Headers.ContentDisposition.FileName.Replace("\"", "")));
            if(!String.IsNullOrEmpty(oRG_jobs_status.vFileName))
                File.Move(oRG_jobs_status.vFileName, Path.Combine(root, serverFile));

        }
        catch (System.Exception e)
        {
            throw;
            //return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, e);
        }
        return CreatedAtRoute("DefaultApi", new { controller = oRG_jobs_status, id = oRG_jobs_status.iJobStatusId }, oRG_jobs_status);
    }

有人可以指导我解决这个问题吗？