ProvideSelectListForEnums

private void ProvideSelectListForEnums(ModelMetadata modelMetadata, Type modelType)
{
    if (modelType != null && modelType.IsEnum && string.IsNullOrEmpty(modelMetadata.TemplateHint))
    {
        modelMetadata.TemplateHint = "SelectList";
        var values = Enum.GetValues(modelType).Cast<object>();
        var items = values.Select(entry => new SelectListItem { Text = Enum.GetName(modelType, entry), Value = entry.ToString() });
        var selectList = new SelectList(items, "Value", "Text", modelMetadata.Model);
        modelMetadata.AdditionalValues.Add("SelectList", selectList);
    }
}