c# - using MultipartFormDataStreamProvider and ReadAsMultipartAsync

Question

How would i go about using MultipartFormDataStreamProvider and Request.Content.ReadAsMultipartAsync in a ApiController?

I have googled a few tutorial but i can't get any of them to work, im using .net 4.5.

This is what i currently got:

public class TestController : ApiController
{
    const string StoragePath = @"T:WebApiTest";
    public async void Post()
    {
        if (Request.Content.IsMimeMultipartContent())
        {
            var streamProvider = new MultipartFormDataStreamProvider(Path.Combine(StoragePath, "Upload"));
            await Request.Content.ReadAsMultipartAsync(streamProvider);
            foreach (MultipartFileData fileData in streamProvider.FileData)
            {
                if (string.IsNullOrEmpty(fileData.Headers.ContentDisposition.FileName))
                {
                    throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.NotAcceptable, "This request is not properly formatted"));
                }
                string fileName = fileData.Headers.ContentDisposition.FileName;
                if (fileName.StartsWith(""") && fileName.EndsWith("""))
                {
                    fileName = fileName.Trim('"');
                }
                if (fileName.Contains(@"/") || fileName.Contains(@""))
                {
                    fileName = Path.GetFileName(fileName);
                }
                File.Copy(fileData.LocalFileName, Path.Combine(StoragePath, fileName));
            }
        }
        else
        {
            throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.NotAcceptable, "This request is not properly formatted"));
        }
    }
}

I get the exception

Unexpected end of MIME multipart stream. MIME multipart message is not complete.

when the await task; runs. Does any one have any idea what i am doing wrong or have a working example in a normal asp.net project using web api.

Answer 1

I resolved the error, i don't understand what this has to do with end of multipart stream but here is the working code:

public class TestController : ApiController
{
    const string StoragePath = @"T:WebApiTest";
    public async Task<HttpResponseMessage> Post()
    {
        if (Request.Content.IsMimeMultipartContent())
        {
            var streamProvider = new MultipartFormDataStreamProvider(Path.Combine(StoragePath, "Upload"));
            await Request.Content.ReadAsMultipartAsync(streamProvider);
            foreach (MultipartFileData fileData in streamProvider.FileData)
            {
                if (string.IsNullOrEmpty(fileData.Headers.ContentDisposition.FileName))
                {
                    return Request.CreateResponse(HttpStatusCode.NotAcceptable, "This request is not properly formatted");
                }
                string fileName = fileData.Headers.ContentDisposition.FileName;
                if (fileName.StartsWith(""") && fileName.EndsWith("""))
                {
                    fileName = fileName.Trim('"');
                }
                if (fileName.Contains(@"/") || fileName.Contains(@""))
                {
                    fileName = Path.GetFileName(fileName);
                }
                File.Move(fileData.LocalFileName, Path.Combine(StoragePath, fileName));
            }
            return Request.CreateResponse(HttpStatusCode.OK);
        }
        else
        {
            return Request.CreateResponse(HttpStatusCode.NotAcceptable, "This request is not properly formatted");
        }
    }
}