ASP.NET MVC 2 Action Method receives null arguments

Question

I'm having a problem with an ASP.NET MVC application that I'm developing. I'm still fairly new at web development and in particular MVC, so please forgive me is this is a really stupid newbie mistake ;-)

I have a view that displays a list of products. Each product has a 'details' link that I want to link to a details view for that product. So, here's the relevant markup from the view:

<% foreach (var item in Model) { %>
<tr>
    <td>
        <%= Html.ActionLink("Edit", "Edit", new { id=item.StockCode.ToString() }) %>
        <%= Html.ActionLink("Details", "Details", new { id=item.StockCode.ToString() })%>
    </td>
    <td>
        <%= Html.Encode(item.StockCode) %>
    </td>
    <td>
        <%= Html.Encode(item.Description) %>
    </td>
</tr>

<% } %>

So far so good. When I hover the mouse over the details link in the web browser, the link shows up as:

http://localhost:40733/RawMaterial/Details/R8517

R8517 is the stock code for the item. So, that's what I expect to see in my Action Method. Here's the Action Method:

//
// GET: /RawMaterial/Details/5

public ActionResult Details(string stockCode)
{
    return View(repository.GetByStockCode(stockCode));
}

But... when the Action Method executes, the parameter (stockCode) is null.

Any thoughts?

Answer 1

The parameter you need to accept shouldn't be "stockCode" is should be "id"

MVC is trying to model bind the "id=item.StockCode.ToString()" to a parameter that is named the same. Your action method should be:

public ActionResult Details(string id)

Answer 2

+1 to DM's answer, but you also have another option. You can register special route for your case. Something like this:

routes.MapRoute("RawMaterial",  "RawMaterial/{action}/{stockCode}", 
    new { controller = "RawMaterial", action = "Index" } );