Model binding two or more collections - asp.net-mvc

Question

Has anyone had any luck model binding two or more collections using the code posted by Phil Haack here: Model Binding To A List?
As an example, I have the below code.
public class Book {
public string Name { get; set; }
}
public class Author {
public string Name { get; set; }
}
public ActionResult Index(List<Book> books, List<Author> authors) {
// Will never model bind two collections.
}
The HTML that I have is:
<input type="hidden" name="books.index" value="1" />
<input type="text" name="books[1].Name" />
<input type="hidden" name="books.index" value="2" />
<input type="text" name="books[2].Name" />
<input type="hidden" name="authors.index" value="1" />
<input type="text" name="authors[1].Name" />
<input type="hidden" name="authors.index" value="1" />
<input type="text" name="authors[1].Name" />
The exception that I get is:
The parameters dictionary contains an invalid entry for parameter 'authors' for method 'System.Web.Mvc.ActionResult Index(System.Collections.Generic.List1[Book], System.Collections.Generic.List1[Author])' in 'HomeController'. The dictionary contains a value of type 'System.Collections.Generic.List1[Book]', but the parameter requires a value of type 'System.Collections.Generic.List1[Author]'. Parameter name: parameters
Am I doing something wrong or is this not supported by ASP.NET MVC?

Answer 1

Your problem is somewhere else, I was unable to reproduce. The following works fine for me:
Model:
public class Book
{
public string Name { get; set; }
}
public class Author
{
public string Name { get; set; }
}
Controller:
public class HomeController : Controller
{
public ActionResult Index()
{
return View();
}
[HttpPost]
public ActionResult Index(List<Book> books, List<Author> authors)
{
return View();
}
}
View:
<% using (Html.BeginForm()) { %>
<input type="text" name="books[0].Name" value="book 1" />
<input type="text" name="books[1].Name" value="book 2" />
<input type="text" name="authors[0].Name" value="author 1" />
<input type="text" name="authors[1].Name" value="author 2" />
<input type="submit" value="OK" />
<% } %>
It successfully binds values back in the POST action.
UPDATE:
I confirm that this is a bug in ASP.NET MVC 3 RC2 which will be fixed in the RTM. As a workaround you could put the following in your Application_Start:
ModelMetadataProviders.Current = new DataAnnotationsModelMetadataProvider();