public ActionResult AddToCart(FormCollection product)
{
int productId = Convert.ToInt32(product["productId"]);
int productQuantity = Convert.ToInt32(product["productQuantity"]);
decimal sellingPrice = Convert.ToDecimal(product["sellingPrice"]);
string productName = product["productName"];
cart.AddShoppingCartItem(productId, productQuantity, sellingPrice, productName);
return(RedirectToAction("Product", new { id = productId }));
}