NameFor generates incorrect name when iterating over collection in editor template

Question

Suppose I have a view typed to a collection, e.g. a List:

@model List

@for(int i = 0; i < Model.Co         


        

Answer 1

Why does NameFor (and therefore EditorFor) exhibit this behaviour in this particular scenario when it works fine for slight variations (i.e. is it intentional and, if so, why)?

It is a bug (link) and it will be fixed with release of ASP.NET MVC 5.

Is there a simple way of working around this behaviour without any of the shortcomings of the above?

Simple:

1. Add ItemViewModel.cshtml editor template with following code:

   @model ItemViewModel
   @Html.EditorFor(m => m.Foo)
   @Html.EditorFor(m => m.Bar) 
   

2. Remove _ItemView.cshtml editor template.

3. Remove [UIHint("_ItemView")] attribute from WrappingViewModel.

A little bit harder:

1. Add ItemViewModel.cshtml editor template (same as above).

2. Modify _ItemView.cshtml:

   @model List
   
   @{
       string oldPrefix = ViewData.TemplateInfo.HtmlFieldPrefix;
   
       try
       {
           ViewData.TemplateInfo.HtmlFieldPrefix = string.Empty;
   
           for (int i = 0; i < Model.Count; i++)
           {
               var item = Model[i];
               string itemPrefix = string.Format("{0}[{1}]", oldPrefix, i.ToString(CultureInfo.InvariantCulture));
               @Html.EditorFor(m => item, null, itemPrefix)
           }
       }
       finally
       {
           ViewData.TemplateInfo.HtmlFieldPrefix = oldPrefix;
       }
   }
   

UPDATE

In case if you don't want to add ItemViewModel.cshtml editor template for the second option then instead of @Html.EditorFor(m => item, null, itemPrefix) you have to write something like that:

@Html.EditorFor(m => item.Foo, null, Html.NameFor(m => item.Foo).ToString().Replace("item", itemPrefix))

@Html.EditorFor(m => item.Bar, null, Html.NameFor(m => item.Bar).ToString().Replace("item", itemPrefix))

NOTE: It's better to wrap that piece of code as extension method