public async Task <IActionResult> Create([Bind("Id,ForYear,Approved,FkUsers,FkBooks,SchoolClassesRequests")] Requests requests)
        {
            if (ModelState.IsValid)
            {
                // Set property of object (Years, Approved)
                requests.FkYears  = StartController._currentYear.Id;
                requests.Approved = 1;

                // if there no user in request set it automaticlly
                if (requests.FkUsers != 0)
                {
                    requests.FkUsers = requests.FkUsers;
                }
                else
                {
                    requests.FkUsers = StartController._currentUser.Id;
                }

                _context.Add(requests);
                await _context.SaveChangesAsync();

                // get the id of selected classes
                var schoolClassesIds = Request.Form["SchoolClassesRequests"];

                // For each id create a schoolclassesrequestd
                foreach (string schoolClassesId in schoolClassesIds)
                {
                    // create an object with parameters
                    SchoolClassesRequests schoolClassesRequest = new SchoolClassesRequests {
                        FkRequests = requests.Id, FkSchoolClasses = Int32.Parse(schoolClassesId)
                    };
                    _context.Add(schoolClassesRequest);
                    await _context.SaveChangesAsync();
                }

                return(RedirectToAction(nameof(Index)));
            }
            return(View(requests));
        }
        public async Task <IActionResult> Edit(int id, [Bind("Id")] Requests requests)
        {
            if (id != requests.Id)
            {
                return(NotFound());
            }

            if (ModelState.IsValid)
            {
                try
                {
                    // get the id of selected classes
                    var schoolClassesIds = Request.Form["SchoolClassesRequests"];

                    // get old school classes
                    var oldSchoolClasses = _context.SchoolClassesRequests.Where(r => r.FkRequests == requests.Id).ToList().Select(s => s.FkSchoolClasses.ToString()).ToArray();

                    // get delete school classes
                    foreach (string el in oldSchoolClasses)
                    {
                        if (!schoolClassesIds.Contains(el))
                        {
                            // Get element to delete it
                            var delEl = _context.SchoolClassesRequests.Where(r => r.FkRequests == requests.Id && r.FkSchoolClasses == Int32.Parse(el)).First();

                            // Delete in database
                            _context.Remove(delEl);
                            await _context.SaveChangesAsync();
                        }
                    }


                    // For each id create a schoolclassesrequestd
                    foreach (string schoolClassesId in schoolClassesIds)
                    {
                        var alreadyExistItem = _context.SchoolClassesRequests.Where(r => r.FkRequests == requests.Id && r.FkSchoolClasses == Int32.Parse(schoolClassesId)).FirstOrDefault();

                        if (alreadyExistItem == null)
                        {
                            // create an object with parameters
                            SchoolClassesRequests schoolClassesRequest = new SchoolClassesRequests {
                                FkRequests = requests.Id, FkSchoolClasses = Int32.Parse(schoolClassesId)
                            };
                            _context.Add(schoolClassesRequest);
                            await _context.SaveChangesAsync();
                        }
                    }
                }
                catch (DbUpdateConcurrencyException)
                {
                    if (!RequestsExists(requests.Id))
                    {
                        return(NotFound());
                    }
                    else
                    {
                        throw;
                    }
                }
                return(RedirectToAction(nameof(Index)));
            }
            return(View(requests));
        }