View models and partial views
Introduces the concept of views, view models and partial views, and provides some examples of how to use these when developing Optimizely Content Management System (CMS 11) websites using ASP.NET Core.
In Optimizely Content Management System (CMS), a template can correspond to an MVC controller and a view. The controller selects the view to display. The view contains the HTML template with embedded code, generating content sent to the client. Another alternative is to use Razor pages as templates.
Views are .cshtml
files stored by default in the Views
folder. Action-specific views, partial views, and layouts are used to reduce repetition. By convention in MVC, the default layout is named _Layout.cshtml
located in the _Views/Shared
folder. See Views (Microsoft).
To avoid repetition, you can create a base controller to be used by the page base class and inherited by other controllers. You can also create view models and partial views to make your views more flexible, for example, when creating menus and other navigation components.
View models
There are several ways of passing data to views. A view model is useful if you want to pass data beyond IContentData
objects into your views. You can define a model type in the view, and pass an instance of this type to the view from the action.
In the following example, you use an interface IPageViewModel
 and a DefaultPageViewModel
 based on a SitePageData
base class.
Example:Â Controller for a Standard page based on a PageController
, using a DefaultPageViewModel
.
namespace MyEPiServerSite.Controllers {
public class StandardPageController: PageController<StandardPage> {
public ActionResult Index(StandardPage currentPage) {
/* Implementation of action. You can create your own view model class that
you pass to the view or you can pass the page type for simpler templates */
DefaultPageViewModel<StandardPage>model = new DefaultPageViewModel<StandardPage>(currentPage);
return View(model);
}
}
}
Example: The DefaultPageViewModel
with the IPageViewModel
interface, and a ContentExtensions
class used for rendering a left navigation section.
namespace MyOptimizelySite.Models.ViewModels {
public class DefaultPageViewModel<T>: IPageViewModel<T> where T: PageData {
public DefaultPageViewModel(T currentPage) {
CurrentPage = currentPage;
Section = ContentExtensions.GetSection(currentPage.ContentLink);
}
public T CurrentPage {
get;
set;
}
public IContent Section {
get;
set;
}
}
}
PropertyFor
 is one of many Optimizely Html
helpers that are frequently used for displaying markup for properties and automatically enable on-page editing of the property when used.
Example:Â View for the Standard page, displaying the left navigation, with page name and main body properties.
@using MyEPiServerSite.Models.Pages
@model MyEPiServerSite.Models.ViewModels.DefaultPageViewModel<StandardPage>
@{
Layout = "~/Views/Shared/Layouts/_LeftNavigation.cshtml";
}
<h1>
@Html.PropertyFor(x => x.CurrentPage.PageName)
</h1>
<div class="row">
<div class="span8 clearfix" >
@Html.PropertyFor(x => x.CurrentPage.MainBody)
</div>
</div>
Partial views
A partial view is a view that is rendered within another view. The HTML output generated is rendered into the calling view. Common layout elements are usually defined in one view, and specific non-reusable layout elements are defined using partial views. See Partial views (Microsoft).
Example: A partial view for rendering a simple top navigation listing subpages to the start page, with links to each page.
@using EPiServer
@inject IContentLoader ContentLoader
@{
var childPages = ContentLoader.GetChildren<PageData>(ContentReference.StartPage);
}
<b>@Html.ContentLink(ContentReference.StartPage)</b>
@foreach (var page in childPages)
{
<b>
@Html.ContentLink(page)
</b>
}
Example:Â The Navigation partial view added to the shared _Layout view, resulting in a top menu display for all pages.
@using EPiServer.Framework.Web.Mvc.Html
@using EPiServer.Core
@model IPageViewModel<SitePageData>
<!DOCTYPE html>
<html>
<head>
<title>@Model.CurrentPage.Name</title>
<link rel="stylesheet" href="some.css" />
</head>
<body>
@await Html.RenderEPiServerQuickNavigatorAsync()
@Html.FullRefreshPropertiesMetaData()
<div class="container">
<div class="row">
<div id="header">
<div class="span2">
<img src="/Static/gfx/logotype.png" />
</div>
<div class="span10">
@{ await Html.RenderPartialAsync("Navigation"); }
</div>
</div>
</div>
<hr />
@RenderBody()
</div>
</body>
</html>
Updated 4 months ago