IEnumerable model property in an ASP.NET MVC 3 Editor Template

Question

I have a model which has an IEnumerable property (warning pseudo-code to follow)

public class PersonModel {
    public string Name { get; set; }
    public IEnumerable<AddressModel> Addresses { get; set; }
}

public class AddressModel {
    public string Name { get; set; }
}

I want to display the Address sub-objects in the same view

Person.cshtml

@model PersonModel

<form>
    <h2>Person</h2>

    @Html.EditorFor(m=>m.Name)

    <ul>@Html.EditorFor(m=>m.Addresses)</ul>

</form>

EditorTemplate/AddressModel

@model AddressModel

<li>@Html.TextboxFor(m=>m.Name)</li>

Marvellous, all works fine

But, being a git, I now want to start using Template Layouts to wrap all my properties in a standard type way and stuff

So I create a string.cshtml and a list.cshtml to do this, with a _Control.cshtml for the layout

EditorTemplates/_Control.cshtml

<div>
    @Html.Label(string.Empty)
    <div class="input">
        @RenderBody()                    

        @Html.ValidationMessage(string.Empty)
    </div>
</div>

EditorTemplates/string.cshtml

@model string
@{    
    Layout = "_Control.cshtml";
}
@Html.TextBox(string.Empty, Model)

(so far yay! but wait.. oh no..)

Here's the trouble

<ul>@Html.EditorFor(m=>m.Addresses)</ul>

from the main view (see above) becomes

@Html.EditorFor(m=>m.Addresses, "List")

EditorTemplates/list.cshtml

@model IEnumerable<object>
@{    
    Layout = "_Control.cshtml";
}
<ul>
    @foreach(var item in Model){
        @Html.EditorFor(m => item)
    }
</ul>

This renders the id and names incorrectly, something like Addresses_item_Name, which does not contain the Id, so adding the id with a for loop

@for (var i = 0; i < Model.Count();i++ ) {
    @Html.EditorFor(m => Model.ElementAt(i))
}

This blows up as the MVC expression helper does not allow anything but arrays, but Addresses has to be IEnumerable<> because EF4.1 does not support .ToArray inside a sub-query ie.

var model = (from p in DataContext.People
             where p.Id = 1
             select new PersonModel {
                 Name = p.Name,
                 Addresses = (from a in p.Addresses
                              select new AddressModel {
                                  Name = a.Name 
                              }).ToArray() // **NOT SUPPORTED**
             }).FirstOrDefault();

Has anyone come up against this? Is there are standard way to do it?

This works, but is it right?

EditorTemplates/list.cshtml

@model IEnumerable<object>
@{    
    Layout = "_Control.cshtml";
    var prefix = ViewData.TemplateInfo.HtmlFieldPrefix;
}
<ul>
    @for (var i = 0; i < Model.Count();i++ ) {
        var item = Model.ElementAt(i);
        ViewData.TemplateInfo.HtmlFieldPrefix = string.Format("{0}[{1}]",prefix, i);
        @Html.EditorFor(m => item, null, string.Empty)
    }
</ul>

The desired structure is

<form>
    <control>
       Person Name Control Elements
    <control>

    <control>
       Address List Control Elements
    <control>
</form>

Answer 1

The EditorFor doesn't allow anything put property types, not methods, this will be why it is dying.

My advice would be to create the template as a single address item, then use a loop outside to edit out each one, or use editorformodel which does that for you.

Si