public async Task <IActionResult> OnGetAsync(int?id)
        {
            if (id == null)
            {
                return(NotFound());
            }

            CarSheet = await _context.CarSheet.FirstOrDefaultAsync(m => m.ID == id);

            if (CarSheet == null)
            {
                return(NotFound());
            }
            ViewData["CarModelId"] = new SelectList(_context.Set <CarModel>(), "ID", "carModelName");
            ViewData["CustomerId"] = new SelectList(_context.Set <Customer>(), "ID", "CustomerName");
            return(Page());
        }
 public IActionResult OnGet()
 {
     ViewData["CarModelId"] = new SelectList(_context.Set <CarModel>(), "ID", "carModelName");
     ViewData["CustomerId"] = new SelectList(_context.Set <Customer>(), "ID", "CustomerName");
     return(Page());
 }