Hi,

I have the following site structure:

• Home
  • Products
    • Product

I am retrieving data and using custom routing and virtual nodes to create a route for single product that looks something like this:

/products/product/23/crayola-crayons-24

There is a button on that product page to Buy Now. When I click that button, I get the following error:

{"The value of parameter 'id' must be either a string or an integer"} in my ProductViewModel at the line:

public ProductViewModel()
            : this(new UmbracoHelper(UmbracoContext.Current).TypedContent((UmbracoContext.Current.PageId)))
        {

        }

The Buy Now link looks like this:

<a href="@Url.Action("AddToCart","ShoppingCart",new{Model})">BUY NOW</a>

ShoppingCartController and AddToCart are as follows:

public class ShoppingCartController : SurfaceController
{
    public ActionResult AddToCart(ProductViewModel product)
    {
        var cart = new ShoppingCart {CreatedOn = DateTime.Now};


        var item = new ShoppingCartItem
        {
            Name = product.Name,
            Price = 699,
            Quantity = 1,
            ProductId = product.ProductId,
            Description = product.ShortDescription,
            Sku = product.PartNumber
        };

        cart.ShoppingCartItems.Add(item);

        using (var db = new ShoppingCartEntities())
        {
            db.SaveChanges();   
        }


        return CurrentUmbracoPage();
    }
}

When I click Buy Now, it never hits the controller, it immediately throws the error mentioned above. I tried using just a regular MVC controller, but then the BUY NOW link doesn't get rendered with the href, so you can't even click on it.

The issue seems to be happening when I pass ProductViewModel which inherits from RenderModel into AddToCart, but if I just pass RenderModel, it hits AddToCart, but RenderModel is null.

What I ended up doing was:

@using (Html.BeginUmbracoForm("AddToCart", "ShoppingCart", new {   @Model} , FormMethod.Post))
    {
        @Html.HiddenFor(x=>x.Name)
        @Html.HiddenFor(x=>x.PartNumber)
        @Html.HiddenFor(x=>x.ProductId)
        @Html.HiddenFor(x=>x.ShortDescription)

        <input type="submit" value="BUY NOW"/>
    }

However, without the hidden fields, when my form posts, the model posted to the action is null. Is there anyway to not use hidden fields?