如何同时向一个web api传递参数和上传图像?

I use this controller:

 public class uploadphotosController : ApiController
    {
        public Task<HttpResponseMessage> Post( )
        {

            // Check if the request contains multipart/form-data.
            if (!Request.Content.IsMimeMultipartContent())
            {
                throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
            }

            string root =HostingEnvironment.MapPath("~/photos");//Burdaki app data klasoru degisecek
            var provider = new MultipartFormDataStreamProvider(root);

            // Read the form data and return an async task.
            var task = Request.Content.ReadAsMultipartAsync(provider).
                ContinueWith<HttpResponseMessage>(t =>
                {
                    if (t.IsFaulted || t.IsCanceled)
                    {
                        return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, t.Exception);
                    }

                    // This illustrates how to get the file names.
                    foreach (MultipartFileData file in provider.FileData)
                    {

                        string fileName = file.LocalFileName;
                        string originalName = file.Headers.ContentDisposition.FileName;


                        FileInfo file2 = new FileInfo(fileName);
                        file2.CopyTo(Path.Combine(root, originalName.TrimStart('"').TrimEnd('"')), true);
                        file2.Delete();

                        //Trace.WriteLine(file.Headers.ContentDisposition.FileName);
                        // Trace.WriteLine("Server file path: " + file.LocalFileName);
                    }
                    return Request.CreateResponse(HttpStatusCode.OK);
                });


            return task;
        }

    }
 public class uploadph