ASP.NET MVC Display Template for strings is used for integers

I recently hit an issue with ASP.NET MVC display templates. Say this is my model:

public class Model
{
    public int ID { get; set; }
    public string Name { get; set; }
}

this is the controller:

public class HomeController : Controller
{
    public ActionResult Index()
    {
        return View(new Model());
    }
}

and this is my view:

<%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<DisplayTemplateWoes.Models.Model>" %>

<!DOCTYPE html>

<html>
<head runat="server">
    <title>Index</title>
</head>
<body>
    <div>
        <%: Html.DisplayForModel() %>
    </div>
</body>
</html>

If I need for some reason a display template for all strings I will create a String.ascx partial view like this:

<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<string>" %>

<%: Model %> (<%: Model.Length %>)

And here is the problem - at runtime the following exception is thrown: "The model item passed into the dictionary is of type 'System.Int32', but this dictionary requires a model item of type 'System.String'"

It seems that String.ascx is used for both the integer and string property of the Model class. I expected it to be used only for the string property - after all it is named String.ascx not Object.ascx or Int32.ascx.

Is this by design? If yes - is it documented somewhere? If not - can it be considered a bug?

foreach (string templateHint in templateHints.Where(s => !String.IsNullOrEmpty(s))) { yield return templateHint; } // We don't want to search for Nullable<T>, we want to search for T (which should handle both T and Nullable<T>) Type fieldType = Nullable.GetUnderlyingType(metadata.RealModelType) ?? metadata.RealModelType; // TODO: Make better string names for generic types yield return fieldType.Name; if (!metadata.IsComplexType) { yield return "String"; } else if (fieldType.IsInterface) { if (typeof(IEnumerable).IsAssignableFrom(fieldType)) { yield return "Collection"; } yield return "Object"; } else { bool isEnumerable = typeof(IEnumerable).IsAssignableFrom(fieldType); while (true) { fieldType = fieldType.BaseType; if (fieldType == null) break; if (isEnumerable && fieldType == typeof(Object)) { yield return "Collection"; } yield return fieldType.Name; } }

<%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<object>" %> <% var model = Model as string; %> <% if (model != null) { %> <%: model %> (<%: model.Length %>) <% } else { %> <%: Model %> <% } %>

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