Question

What is your way of passing data to Master Page (using ASP.NET MVC) without breaking MVC rules?

Personally, I prefer to code abstract controller (base controller) or base class which is passed to all views.

Answer 1

If you prefer your views to have strongly typed view data classes this might work for you. Other solutions are probably more correct but this is a nice balance between design and practicality IMHO.

The master page takes a strongly typed view data class containing only information relevant to it:

public class MasterViewData {     public ICollection<string> Navigation { get; set; } } 

Each view using that master page takes a strongly typed view data class containing its information and deriving from the master pages view data:

public class IndexViewData : MasterViewData {     public string Name { get; set; }     public float Price { get; set; } } 

Since I don’t want individual controllers to know anything about putting together the master pages data I encapsulate that logic into a factory which is passed to each controller:

public interface IViewDataFactory {     T Create<T>()         where T : MasterViewData, new() }  public class ProductController : Controller {     public ProductController(IViewDataFactory viewDataFactory)     ...      public ActionResult Index()     {         var viewData = viewDataFactory.Create<ProductViewData>();          viewData.Name = 'My product';         viewData.Price = 9.95;          return View('Index', viewData);     } } 

Inheritance matches the master to view relationship well but when it comes to rendering partials / user controls I will compose their view data into the pages view data, e.g.

public class IndexViewData : MasterViewData {     public string Name { get; set; }     public float Price { get; set; }     public SubViewData SubViewData { get; set; } }  <% Html.RenderPartial('Sub', Model.SubViewData); %> 

This is example code only and is not intended to compile as is. Designed for ASP.Net MVC 1.0.