MVC ASP.NET CORE, Uploading files sometime the file being uploaded become corrupted / size 0 byte

Question

So I am trying to upload files in my mvc core and it works, however, sometime the file being uploaded is like corrupted or size 0 bytes. Does anyone ever experienced something like this? The initial file size being uploaded is not large at all.

Thanks.

public IActionResult UploadCertificateFile(IFormFile UploadCertificate)
        {
            var parsedContentDisposition =
                   ContentDispositionHeaderValue.Parse(UploadCertificate.ContentDisposition);
            var filename = Path.Combine(_hostingEnvironment.WebRootPath,
                "Uploads", parsedContentDisposition.FileName.Trim('"'));
            using (var stream = System.IO.File.OpenWrite(filename))
            {
                UploadCertificate.CopyToAsync(stream);
            }
            return RedirectToAction("Index");
        }

Answer 1

I think the problem here is using CopyToAsync and not calling await, I think you should make your method declaration async Task and call await in UploadCertificate.CopyToAsync line, or just use CopyTo (but is better for I/O to make it async)

File might not be copied fully, when you thread is killed, so this is why your file is corrupted.