gistfile1.cs

private readonly IWebService _webService;


public DocumentController(IWebService webService)
{
    _webService = webService;
}

public ActionResult Index(int? id)
{
    var indexViewModel = new IndexViewModel();

    if (id == null)
    {
        indexViewModel.Title = "Select a Category:";
        indexViewModel.List = webService.GetCategories();
    }
    else
    {
        Session["CategoryID"] = (int)id; // Not sure what this is for. I know what sessions are for....

        indexViewModel.Title = "Select a Definition:";
        indexViewModel.CategoryId = id;
        indexViewModel.List = webService.GetDefinitions((int)id);
    }

    if (list == null || list.Count <= 0)
        indexViewModel.Description = "None found.";

    return View(indexViewModel);
}