HttpClient: How to upload multiple files at once

Question

I am trying to upload muliple files using System.Net.Http.HttpClient.

using (var content = new MultipartFormDataContent()) {    content.Add(new StreamContent(imageStream), "image", "image.jpg");    content.Add(new StreamContent(signatureStream), "signature", "image.jpg.sig");     var response = await httpClient.PostAsync(_profileImageUploadUri, content);    response.EnsureSuccessStatusCode(); } 

this only sends mulipart/form-data, but i expected multipart/mixed somewhere in the post.

UPDATE: Ok, i got around.

using (var content = new MultipartFormDataContent()) {     var mixed = new MultipartContent("mixed")     {         CreateFileContent(imageStream, "image.jpg", "image/jpeg"),         CreateFileContent(signatureStream, "image.jpg.sig", "application/octet-stream")     };      content.Add(mixed, "files");      var response = await httpClient.PostAsync(_profileImageUploadUri, content);     response.EnsureSuccessStatusCode(); }  private StreamContent CreateFileContent(Stream stream, string fileName, string contentType) {     var fileContent = new StreamContent(stream);     fileContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("file") {FileName = fileName};     fileContent.Headers.ContentType = new MediaTypeHeaderValue(contentType);     return fileContent; } 

This looks correct on wire shark. but i do not see the files in my controller.

[HttpPost] public ActionResult UploadProfileImage(IEnumerable<HttpPostedFileBase> postedFiles) {     if(postedFiles == null)         return new HttpStatusCodeResult(HttpStatusCode.BadRequest);      // more code here } 

postedFiles is still null. Any ideas?

Answer 1

Nailed it. But behaviour is strange.

using (var content = new MultipartFormDataContent()) {     content.Add(CreateFileContent(imageStream, "image.jpg", "image/jpeg"));     content.Add(CreateFileContent(signatureStream, "image.jpg.sig", "application/octet-stream"));      var response = await httpClient.PostAsync(_profileImageUploadUri, content);     response.EnsureSuccessStatusCode(); }  private StreamContent CreateFileContent(Stream stream, string fileName, string contentType) {     var fileContent = new StreamContent(stream);     fileContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")      {          Name = "\"files\"",          FileName = "\"" + fileName + "\""     }; // the extra quotes are key here     fileContent.Headers.ContentType = new MediaTypeHeaderValue(contentType);                 return fileContent; }  [HttpPost] public ActionResult UploadProfileImage(IList<HttpPostedFileBase> files) {     if(files == null || files.Count != 2)         return new HttpStatusCodeResult(HttpStatusCode.BadRequest);      // more code }