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

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

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!EmployeeExists(Employee.ID))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

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

            //if (LastSalaryHistory != null)
            //{


            //}

            NewSalaryHistory = new SalaryHistory
            {
                EmployeeID         = Employee.ID,
                SalaryPeriodBegan  = Employee.DateHired,
                SalaryForThePeriod = Employee.Salary,
                SalaryPeriodEnded  = DateTime.Now
            };

            LastSalaryHistory = await _context.SalaryHistory.OrderByDescending(s => s.ID).FirstOrDefaultAsync(s => s.EmployeeID == Employee.ID);

            LastSalaryHistory.SalaryPeriodEnded = Employee.DateHired;
            _context.SalaryHistory.Update(LastSalaryHistory);

            _context.Attach(Employee).State = EntityState.Modified;
            _context.SalaryHistory.Add(NewSalaryHistory);

            try
            {
                await _context.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!EmployeeExists(Employee.ID))
                {
                    return(NotFound());
                }
                else
                {
                    throw;
                }
            }

            return(RedirectToPage("/Employees"));
        }