public IActionResult Create([Bind("baseId,retailPrice,wholeSalePrice,productKDV,barcodeID, name,sellersID,detailsId")] baseproduct baseproduct)
        {
            string error_msg = "";

            if (ModelState.IsValid)
            {
                if (baseproduct.barcodeID.Length == 13)
                {
                    barcodeController barcode    = new barcodeController(_context);
                    string            checkDigit = barcode.calcCheckDigit(baseproduct.barcodeID.Substring(0, 12));
                    if (checkDigit != baseproduct.barcodeID.Substring(12, 1))
                    {
                        error_msg = "Barkod kontrol karakteri hatalı.";
                    }
                }
                else
                {
                    error_msg = "Barkod Uzunluğu 13 karakter olmalı";
                }
                if (error_msg != "")
                {
                    ModelState.AddModelError("barkod", error_msg);
                }
                else
                {
                    _context.Add(baseproduct);
                    _context.SaveChanges();
                    _context.SaveChanges();
                    return(RedirectToAction(nameof(Index)));
                }
            }
            return(View(baseproduct));
        }