Using Interfaces

    When using compositions, Models Builder generates an interface for the composed model, which enables us to not have to switch back to using Value() for the composed properties.

    A common use-case for this is if you have a separate composition for the "SEO properties" Page Title and Page Description.

    You would usually use this composition on both your Home and Textpage document types. Since both Home and Textpage will implement the generated ISeoProperties interface, you will still be able to use the simpler models builder syntax (e.g. Model.PageTitle).

    However, you won't be able to use the nice models builder syntax on any master template, since a master template needs to be bound to a generic IPublishedContent. So you'd have to resort to the ever-so-slightly clumsier Model.Value("pageTitle") syntax to render these properties. It is possible to solve this issue of master templating, by using partial views, to render the SEO specific properties.

    Render with a partial

    If you create a partial and change the first line to use the interface name for the model binding, you can use the nice Models Builder syntax when rendering the properties, like this:

    @inherits Umbraco.Cms.Web.Common.Views.UmbracoViewPage<ISeoProperties>
    <title>@Model.PageTitle</title>
    <meta name="description" content="@Model.PageDescription">
    

    You can then render the partial from your Master Template with something like this (assuming the partial is named Metatags.cshtml):

    <head>
        @Html.Partial("Metatags")
    </head>
    @RenderBody()
    

    It's important to note though, that this master template will only work for content types that use the Seo Properties composition.