How to solve file upload error in Postman?

Question

I use file upload with webapi in my project. I am testing with Postman. However, Request.Content.IsMimeMultipartContent() always returns false.

Postman screenshot:

FileUploadController Code:

public async Task<HttpResponseMessage> UserImageUpload()
    {
        try
        {
            if (!Request.Content.IsMimeMultipartContent())
            {
                throw new HttpResponseException(HttpStatusCode.UnsupportedMediaType);
            }

            var userImageUploadPath = HttpContext.Current.Server.MapPath(CommonParameters.UserProfileImageServerPath);
            var streamProvider = new CustomMultipartFormDataStreamProvider(userImageUploadPath);
            await Request.Content.ReadAsMultipartAsync(streamProvider);

            var files = new List<string>();
            foreach (MultipartFileData file in streamProvider.FileData)
            {
                files.Add(Path.GetFileName(file.LocalFileName));
            }

            return Request.CreateResponse(HttpStatusCode.OK, files);
        }
        catch (Exception exception)
        {
            logger.ErrorFormat("An error occured in UserImageUpload() Method - Class:FileUploadController - Message:{0}", exception);
            return Request.CreateResponse(HttpStatusCode.BadRequest);
        }
    }

Answer 1

This is Postman bug. Try removing the Content-Type header. When sending the actual Post, the browser will automatically add the proper header and create the boundary.

Answer 2

There is no need to mention Content-Type in headers in Postman, I tried sending attachments without Content-Type it works fine for me. When i used Content-Type: multipart/formdata it throws an error saying "Could not get any response". Postman sends your file attachments also with Content-Type →text/plain; charset=utf-8.

Answer 3

There are few things to consider:

1) Don't send any Content Type Header if you are using Postman

2) Specify the Key for your choosen file in Body (PFB Screenshot for your reference)

Answer 4

You need to uncheck Content-Type if you have it checked, and let Postman add it for you, like in this picture:

Answer 5

Might by a bit late. I encountered the same error in ARC and resolved by providing a name for the file field (after the blue check mark on your second screenshot)