public async Task <IActionResult> OnPostAsync()
        {
            if (!ModelState.IsValid)
            {
                return(Page());
            }

            if (!(AllowedUsers is null))
            {
                Document.AllowedUsers = AllowedUsers.Split(",").ToList().Select(a => a.Trim()).ToArray();
            }

            var test = _context.DocumentAnnotations.AsNoTracking().SingleOrDefault(m =>
                                                                                   m.DocumentId == Document.DocumentId &&
                                                                                   m.UserId == User.FindFirst(ClaimTypes.NameIdentifier).Value);

            if (test is null)
            {
                return(NotFound());
            }

            _context.Attach(Document).State = EntityState.Modified;
            await _context.SaveChangesAsync();


            return(RedirectToPage("./Index"));
        }
        public async Task <IActionResult> OnPostAsync()
        {
            if (!ModelState.IsValid)
            {
                return(Page());
            }

            _context.Attach(Text).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!TextExists(Text.TextId))
                {
                    return(NotFound());
                }

                throw;
            }

            return(RedirectToPage("./Index"));
        }