Upload in the database and download it in a special folder of the project in ASP.NET Core v5

Question

I want the file that I uploaded in the documentUploadProvinceLevels database table to be able to be downloaded and to be saved in a special wwwroot folder after downloading. I implemented the file upload part, but I don't know what to do for downloading. please help me

Upload code:

public bool UploadAvatarProvinceDB(IFormFile file, RegisterViewModel document)
{
        if (file != null)
        {
            if (file.Length > 0)
            {
                int department = 1;
                document.uploadDate = DateTime.Now;
                document.fileName = "no-document";
                document.description = "ثبت تصویر پرسنل";
                var docName = Path.GetFileName(file.FileName);
                var fileExtension = Path.GetExtension(docName);
                var newFileName = String.Concat(document.nationalCode, fileExtension);

                var objfiles = new DocumentUploadProvinceLevel()
                {
                    id = 0,
                    fileName = newFileName,
                    uploadDate = DateTime.Now,
                    title = "تصویر پرسنل",
                    fileFormat = fileExtension,
                    userId = document.nationalCode,
                    description = document.description,
                    department = department,
                    IsDelete=false
                };

                using (var target = new MemoryStream())
                {
                    file.CopyTo(target);
                    objfiles.dataBytes = target.ToArray();
                }
                _context.documentUploadProvinceLevels.Add(objfiles);
                _context.SaveChanges();

                return true;
            }
        }

        return false;
}

documentUploadProvinceLevels table:

Answer 1

You can use FileStream. Below is a working demo, you can refer to it.

public async Task<bool> Download(int id)
{
    byte[] bytes;
    var item = _context.documentUploadProvinceLevels.Where(d => d.id == id).FirstOrDefault();
    if (item != null)
    {
        var fileName = item.fileName;
        bytes = item.dataBytes;
        var filePath = Path.Combine(Directory.GetCurrentDirectory(), @"wwwroot\files", fileName);
        using (var fileStream = new FileStream(filePath, FileMode.Create))
        {
            await fileStream.WriteAsync(bytes);
        }
        return true;
    }
    return false;
}

Test Result: