Custom Model Binder, asp.net mvc 2 rtm 2, Parsing ID to ComplexModel - asp.net-mvc-2

Question

I have found myself with at little problem, and I think a custom model binder is the way to go.
My Domain model looks like this,readly standard
I got a Page and a Template. The Page has the Template as a ref.
So the Default asp.net mvc Binder, does not know how to bind it, therefore I need to make some rules for it. (Custom Model Binder)
public class PageTemplate
{
public virtual string Title { get; set; }
public virtual string Content { get; set; }
public virtual DateTime? Created { get; set; }
public virtual DateTime? Modified { get; set; }
}
public class Page
{
public virtual string Title { get; set; }
public virtual PageTemplate Template { get; set; }
public virtual string Content { get; set; }
public virtual DateTime? Created { get; set; }
public virtual DateTime? Modified { get; set; }
}
So I have Registreted the ModelBinder in globals.asax
ModelBinders.Binders.Add(typeof(Cms.Domain.Entities.Page),
new Cms.UI.Web.App.ModelBinders.PageModelBinder(
new Services.GenericApplicationService<Cms.Domain.Entities.Page>().GetEntityStore()
)
);
My ModelBinder tage a paremeter, witch is my Repository, where I get all my Entities ( Page, Template )
My Controller for a Page looks like this.
I have posted into a Create Controler, it does not matter for now, if it was a Update method.
Since I in this case have a dropdown, that represents the Template, I will get an ID in my form collection.
I then call: TryUpdateModel and I got a hit in my PageModelBinder.
[AcceptVerbs(HttpVerbs.Post), ValidateAntiForgeryToken]
[ValidateInput(false)]
public ActionResult Create(FormCollection form)
{
Page o = new Page();
string[] exclude = new { "Id" }
if (base.TryUpdateModel<Page>(o, string.Empty, null, exclude, form.ToValueProvider()))
{
if (ModelState.IsValid)
{
this.PageService.Add(o);
this.CmsViewData.PageList = this.PageService.List();
this.CmsViewData.Messages.AddMessage("Page is updated.", MessageTypes.Succes);
return View("List", this.CmsViewData);
}
}
return View("New", this.CmsViewData);
}
So I end op with the Model Binder.
I have search the internet dry for information, but im stock.
I need to get the ID from the FormCollection, and parse it to at Model from my IEntityStore.
But how ?
public class PageModelBinder : IModelBinder
{
public readonly IEntityStore RepositoryResolver;
public PageModelBinder(IEntityStore repositoryResolver)
{
this.RepositoryResolver = repositoryResolver;
}
public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
if (bindingContext == null)
{
throw new ArgumentNullException("bindingContext");
}
if (modelType == typeof(Cms.Domain.Entities.Page))
{
// Do some magic
// Get the Id from Property and bind it to model, how ??
}
}
}
// Dennis
I hope, my problom is clear.

Answer 1

Did find a work around.
I download the sourcecode for asp.net r2 rtm 2
And did copy all code for the default ModelBinder, and code it need. Did some minor change, small hacks.
the work around is doing a little hack in this method:
[SuppressMessage("Microsoft.Globalization", "CA1304:SpecifyCultureInfo", MessageId = "System.Web.Mvc.ValueProviderResult.ConvertTo(System.Type)",
Justification = "The target object should make the correct culture determination, not this method.")]
[SuppressMessage("Microsoft.Design", "CA1031:DoNotCatchGeneralExceptionTypes",
Justification = "We're recording this exception so that we can act on it later.")]
private static object ConvertProviderResult(ModelStateDictionary modelState, string modelStateKey, ValueProviderResult valueProviderResult, Type destinationType)
{
try
{
object convertedValue = valueProviderResult.ConvertTo(destinationType);
return convertedValue;
}
catch (Exception ex)
{
try
{
// HACK if the binder still fails, try get the entity in db.
Services.GenericApplicationService<Cms.Domain.Entities.PageTemplate> repo;
repo = new Services.GenericApplicationService<Cms.Domain.Entities.PageTemplate>();
int id = Convert.ToInt32(valueProviderResult.AttemptedValue);
object convertedValue = repo.Retrieve(id);
return convertedValue;
}
catch (Exception ex1)
{
modelState.AddModelError(modelStateKey, ex1);
return null;
}
}
}
This question is closed.