I exposed the protected UpdateModel in my controller:

public void UpdateModel(BusinessSavingsRequest bsr, string[] keys)
{
base.UpdateModel(bsr, keys);
}

and then call it from my binder:

public object GetValue(ControllerContext controllerContext, string modelName, Type modelType, ModelStateDictionary modelState)
{
BusinessSavingsRequest bsr = new BusinessSavingsRequest();
string[] properties = typeof(BusinessSavingsRequest).GetProperties().Select(p => p.Name).ToArray();
((MvcApplication.Controllers.BusinessSavingsController)controllerContext.Controller).UpdateModel(bsr, properties);
return bsr;
}

Perhaps if this is all it needed to do I wouldnt have a custom binder for the type.

I exposed the protected UpdateModel in my controller:

public void UpdateModel(BusinessSavingsRequest bsr, string[] keys)
{
base.UpdateModel(bsr, keys);
}

and then call it from my binder:

public object GetValue(ControllerContext controllerContext, string modelName, Type modelType, ModelStateDictionary modelState)
{
BusinessSavingsRequest bsr = new BusinessSavingsRequest();
string[] properties = typeof(BusinessSavingsRequest).GetProperties().Select(p => p.Name).ToArray();
((MvcApplication.Controllers.BusinessSavingsController)controllerContext.Controller).UpdateModel(bsr, properties);
return bsr;
}

Perhaps if this is all it needed to do I wouldnt have a custom binder for the type.

How do you use it? Why the need to 'register' it.

Seems to me if you pass a complex type as a parameter, it would map the form variables to the type with reflection – and only if you need to have more complex mapping would you create a specific binder…

Thanks for the heads up.

Thanks for the heads up.