The scenario: Given a blog application, with the following layout
with two possible usages – a post page: and a homepage:
Let’s define the view model:
PostData: string Title string Body PostView PostData Post; HomepageView PostData Posts LayoutView Tuple<string, int> Archive Tuple<string, int> TagCloud string Similar
_Layout.cshtml – obvious
Post.cshtml – given a PostData instance will render Title and Body
PostPage.cshtml – given a PostData, will call Post.cshtml and then render “add comment” form
Homepage.cshtml – given PostData array, will iterate and call Post.cshtml for each post
How data moves around:
Controller is passing PostView (or HomepageView) along with LayoutView to the views
Post.cshtml should only see its parameters, not the layout’s (which are passed but are not interesting within the post template).
same goes for the other views
All views should be able to “see” a shared parameter named “IsCurrentUserAdmin”
Given that I want typed access to the view parameters in the view (for the sake of intellisense and refactorings), how would I model and pass the data around?
I’ve pseudo-code-grade written two options: the first is to use inheritence in the view model to achieve type-ness, on the expense of flexibility (composition is difficult with class hierarchy, and you need to be aware of and grab the viewModel instance in various places). The second is flexible (use the ViewData dictionary) but getting type-ness is cumbersome and partial (strings scattered around, casting needed etc.)
see https://gist.github.com/1272269 if the gist widget does not load in-place I do have a solution that works for me With the many years that I’ve been writing complex web apps using various ASP.NET frameworks and almost always with c# based, static-typed view engines, I have a solution that works very nicely for me. But I want to be aware of the MVC3 canonical / textbox way So for all you MVC3 ninja’s out there – please describe your way of doing it.
I will describe my approach in an upcoming post and I’d appreciate any input on it