public async Task <IActionResult> PutComment(int id, Comment comment)
        {
            if (id != comment.Id)
            {
                return(BadRequest());
            }

            _context.Entry(comment).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!CommentExists(id))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

            return(NoContent());
        }
        public async Task <IActionResult> PutGroupMember(int id, GroupMember groupMember)
        {
            if (id != groupMember.Id)
            {
                return(BadRequest());
            }

            _context.Entry(groupMember).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!GroupMemberExists(id))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

            return(NoContent());
        }
        public async Task <IActionResult> PutMessage(int id, Message message)
        {
            if (id != message.Id)
            {
                return(BadRequest());
            }

            _context.Entry(message).State = EntityState.Modified;

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!MessageExists(id))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

            return(NoContent());
        }