Dynamic Anonymous type in Razor causes RuntimeBinderException

Question

I'm getting the following error:

'object' does not contain a definition for 'RatingName'

When you look at the anonymous dynamic type, it clearly does have RatingName.

I realize I can do this with a Tuple, but I would like to understand why the error message occurs.

Answer 1

Anonymous types having internal properties is a poor .NET framework design decision, in my opinion.

Here is a quick and nice extension to fix this problem i.e. by converting the anonymous object into an ExpandoObject right away.

public static ExpandoObject ToExpando(this object anonymousObject)
{
    IDictionary<string, object> anonymousDictionary =  new RouteValueDictionary(anonymousObject);
    IDictionary<string, object> expando = new ExpandoObject();
    foreach (var item in anonymousDictionary)
        expando.Add(item);
    return (ExpandoObject)expando;
}

It's very easy to use:

return View("ViewName", someLinq.Select(new { x=1, y=2}.ToExpando());

Of course in your view:

@foreach (var item in Model) {
     <div>x = @item.x, y = @item.y</div>
}