Planet ASP.NET MVC

The release for MvcSiteMapProvider 2.1.0 has just been posted on CodePlex. MvcSiteMapProvider is, as the name implies, an ASP.NET MVC SiteMapProvider implementation for the ASP.NET MVC framework. Targeted at ASP.NET MVC 2, it provides sitemap XML functionality and interoperability with the classic ASP.NET sitemap controls, like the SiteMapPath control for rendering breadcrumbs and the Menu control.

Next to a brand new logo, the component has been patched up with several bugfixes, the visibility attribute is back (in a slightly cooler reincarnation) and a number of new extension points have been introduced. Let’s give you a quick overview…

Extension points

MvcSiteMapProvider is built wih extensibility in mind. All extension point contracts are defined in the MvcSiteMapProvider.Extensibility namespace. The sample application on the downloads page contains several custom implementations of these extension points.

Global extension points (valid for the entire provider and all nodes)

These extension points can be defined when Registering the provider.

  Node key generator

Keys for sitemap nodes are usually automatically generated by the MvcSiteMapProvider core. If, for reasons of accessing sitemap nodes from code, the generated keys should follow other naming rules, a custom MvcSiteMapProvider.Extensibility.INodeKeyGenerator implementation can be written.

  Controller type resolver

In order to resolve a controller type and action method related to a specific sitemap node, a MvcSiteMapProvider.Extensibility.IControllerTypeResolver is used. This should normally not be extended, however if you want to make use of other systems for resolving controller types and action methods, this is the logical extension point.

  Action method parameter resolver

Action method parameters are resolved by using ASP.NET MVC’s ActionDescriptor class. If you want to use a custom system for this, a MvcSiteMapProvider.Extensibility.IActionMethodParameterResolver implementation can be specified.

  ACL module

To determine whether a sitemap node is accessible to a specific user, a MvcSiteMapProvider.Extensibility.IAclModule implementation is used. MvcSiteMapProvider uses two of these modules by default: access is granted or denied by checking for [Authorize] attributes on action methods, followed by the roles attribute that can be specified in the sitemap XML.

  URL resolver

URLs are generated by leveraging a MvcSiteMapProvider.Extensibility.ISiteMapNodeUrlResolver implementation. If, for example, you want all URLs generated by MvcSiteMapProvider to be in lowercase text, a custom implementation can be created.

  Visibility provider

In some situations, nodes should be visible in the breadcrumb trail but not in a complete sitemap. This can be solved using the MvcSiteMapProvider.Extensibility.ISiteMapNodeVisibilityProvider extension point that can be specified globally for every node in the sitemap or granularly on a specific sitemap node. A sample is available on the Advanced node visibility page.

Node-specific extenion points (valid for a single node)

These extension points can be defined when Creating a first sitemap.

  Dynamic node provider

In many web applications, sitemap nodes are directly related to content in a persistent store like a database.For example, in an e-commerce application, a list of product details pages in the sitemap maps directly to the list of products in the database. Using dynamic sitemaps, a small class implementing MvcSiteMapProvider.Extensibility.IDynamicNodeProvider or extending MvcSiteMapProvider.Extensibility.DynamicNodeProviderBase can be provided to the MvcSiteMapProvider offering a list of dynamic nodes that should be incldued in the sitemap. This ensures the product pages do not have to be specified by hand in the sitemap XML.

A sample can be found on the Dynamic sitemaps page.

  URL resolver

URLs are generated by leveraging a MvcSiteMapProvider.Extensibility.ISiteMapNodeUrlResolver implementation. If, for example, you want the URL for a sitemap node generated by MvcSiteMapProvider to be in lowercase text, a custom implementation can be created.

  Visibility provider

In some situations, nodes should be visible in the breadcrumb trail but not in a complete sitemap. This can be solved using the MvcSiteMapProvider.Extensibility.ISiteMapNodeVisibilityProvider extension point that can be specified globally for every node in the sitemap or granularly on a specific sitemap node. A sample is available on the Advanced node visibility page.

Conclusion

Only one conclusion: grab the latest bits and start playing with them! And feel free to bug me with feature requests and issues found.

Also, follow me on Twitter for updates on this project.

Back in March, I blogged about an experimental MvcSiteMap provider I was building. Today, I am proud to announce that it is stable enough to call it version 1.0! Download MvcSiteMapProvider 1.0 over at CodePlex.

Ever since the source code release I did back in March, a lot of new features have been added, such as HtmlHelper extension methods, attributes, dynamic parameters, … I’ll leave most of them up to you to discover, but there are some I want to quickly highlight.

ACL module extensibility

By default, MvcSiteMap will make nodes visible or invisible based on [Authorize] attributes that are placed on controllers or action methods. If you have implemented your own authentication mechanism, this may no longer be the best way to show or hide sitemap nodes. By implementing and registering the IMvcSiteMapAclModule interface, you can now plug in your own visibility logic.

Dynamic parameters

Quite often, action methods have parameters that are not really bound to a sitemap node. For instance, take a paging parameter. You may ignore this one safely when determining the active sitemap node: /Products/List?page=1 and /Products/List?page=2 should both have the same menu item highlighted. This is where dynamic parameters come in handy: MvcSiteMap will completely ignore the specified parameters when determining the current node.

The above sitemap node will always be highlighted, whatever the value of “page” is.

SiteMapTitle action filter attribute

In some situations, you may want to dynamically change the SiteMap.CurrentNode.Title in an action method. This can be done manually by setting  SiteMap.CurrentNode.Title, or by adding the SiteMapTitle action filter attribute.

Imagine you are building a blog and want to use the Blog’s Headline property as the site map node title. You can use the following snippet:

You can also use a non-strong typed ViewData value as the site map node title:

HtmlHelper extension methods

MvcSiteMap provides different HtmlHelper extension methods which you can use to generate SiteMap-specific HTML code on your ASP.NET MVC views. Here’s a list of available HtmlHelper extension methods.

• HtmlHelper.Menu() – Can be used to generate a menu
• HtmlHelper.SiteMap() – Can be used to generate a list of all pages in your sitemap
• HtmlHelper.SiteMapPath() – Can be used to generate a so-called “breadcrumb trail”

The MvcSiteMap release can be found on CodePlex.