Question

I’m building a web-application with MS MVC 3 and have run into an issue, probably due to a hole in my understanding of model-binding.

Firstly, I have a fairly standard model (irrelevant stuff omitted for brevity, names changed to protect the privacy of innocent objects):

public class ModelBase
{
    public int Id { get; set; }
}

 public class Order : ModelBase
{
    public List<Product> Products { get; set; }
}

public class Product : ModelBase
{
    public int OrderId { get; set;}
}

For displaying and editing these, I have a View strongly typed to the Order class, containing a Partial View which is strongly typed to the Product class. The top of the partial view looks like this:

@model Product

@Html.ValidationSummary(true)
@Html.HiddenFor(model => model.Id)
@Html.HiddenFor(model => model.OrderId)
//loads of actual editable properties

I insert the partial into the main view like this:

@Html.Partial("EditorTemplates/Product", Model.Products.First())

…and when the view is rendered in the browser, the “Id” hidden input contains the Id of the Order, not the Id of the Product that I expect and need 🙁

What am I missing? Can it be fixed without changing the structure of the model and views?

Answer 1

On changing my test project I can confirm that

/Home/Index?id=33

or

/Home/Index/33

DOES overwrite the model value. Can you remove this parameter from the url?