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title	author	description	monikerRange	ms.author	ms.custom	ms.date	uid
Razor Pages route and app conventions in ASP.NET Core	tdykstra	Discover how route and app model provider conventions help you control page routing, discovery, and processing.	>= aspnetcore-2.1	tdykstra	mvc	02/07/2020	razor-pages/razor-pages-conventions

Razor Pages route and app conventions in ASP.NET Core

:::moniker range=">= aspnetcore-6.0"

Learn how to use page route and app model provider conventions to control page routing, discovery, and processing in Razor Pages apps.

To specify a page route, add route segments, or add parameters to a route, use the page's @page directive. For more information, see Custom routes.

There are reserved words that can't be used as route segments or parameter names. For more information, see Routing: Reserved routing names.

View or download sample code (how to download)

Scenario	The sample demonstrates
Model conventions Conventions.Add xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageRouteModelConvention xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageApplicationModelConvention xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageHandlerModelConvention	Add a route template and header to an app's pages.
Page route action conventions xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddFolderRouteModelConvention%2A xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddPageRouteModelConvention%2A xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.AddPageRoute%2A	Add a route template to pages in a folder and to a single page.
Page model action conventions xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddFolderApplicationModelConvention%2A xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddPageApplicationModelConvention%2A xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.ConfigureFilter%2A (filter class, lambda expression, or filter factory)	Add a header to pages in a folder, add a header to a single page, and configure a filter factory to add a header to an app's pages.

Razor Pages conventions are configured using an xref:Microsoft.Extensions.DependencyInjection.MvcServiceCollectionExtensions.AddRazorPages%2A overload that configures xref:Microsoft.AspNetCore.Mvc.RazorPages.RazorPagesOptions. The following convention examples are explained later in this topic:


var builder = WebApplication.CreateBuilder(args);

builder.Services.AddRazorPages(options =>
    {
        options.Conventions.Add( ... );
        options.Conventions.AddFolderRouteModelConvention(
            "/OtherPages", model => { ... });
        options.Conventions.AddPageRouteModelConvention(
            "/About", model => { ... });
        options.Conventions.AddPageRoute(
            "/Contact", "TheContactPage/{text?}");
        options.Conventions.AddFolderApplicationModelConvention(
            "/OtherPages", model => { ... });
        options.Conventions.AddPageApplicationModelConvention(
            "/About", model => { ... });
        options.Conventions.ConfigureFilter(model => { ... });
        options.Conventions.ConfigureFilter( ... );
    });
}

Route order

Routes specify an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel.Order* for processing (route matching).

Route order	Behavior
-1	The route is processed before other routes are processed.
0	Order isn't specified (default value). Not assigning `Order` (`Order = null`) defaults the route `Order` to 0 (zero) for processing.
1, 2, … n	Specifies the route processing order.

Route processing is established by convention:

Routes are processed in sequential order (-1, 0, 1, 2, … n).
When routes have the same Order, the most specific route is matched first followed by less specific routes.
When routes with the same Order and the same number of parameters match a request URL, routes are processed in the order that they're added to the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.

If possible, avoid depending on an established route processing order. Generally, routing selects the correct route with URL matching. If you must set route Order properties to route requests correctly, the app's routing scheme is probably confusing to clients and fragile to maintain. Seek to simplify the app's routing scheme. The sample app requires an explicit route processing order to demonstrate several routing scenarios using a single app. However, you should attempt to avoid the practice of setting route Order in production apps.

Razor Pages routing and MVC controller routing share an implementation. Information on route order in the MVC topics is available at Routing to controller actions: Ordering attribute routes.

Model conventions

Add a delegate for xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageConvention to add model conventions that apply to Razor Pages.

Add a route model convention to all pages

Use xref:Microsoft.AspNetCore.Mvc.RazorPages.RazorPagesOptions.Conventions to create and add an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageRouteModelConvention to the collection of xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageConvention instances that are applied during page route model construction.

The sample app contains the GlobalTemplatePageRouteModelConvention class to add a {globalTemplate?} route template to all of the pages in the app:

[!code-csharp]

In the preceding code:

The xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageRouteModel is passed to the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageRouteModelConvention.Apply%2A method.
The PageRouteModel.Selectors gets the count of selectors.
A new xref:Microsoft.AspNetCore.Mvc.ApplicationModels.SelectorModel is added which contains a xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel

Razor Pages options, such as adding xref:Microsoft.AspNetCore.Mvc.RazorPages.RazorPagesOptions.Conventions, are added when Razor Pages is added to the service collection. For an example, see the sample app.

[!code-csharp]

Consider the GlobalTemplatePageRouteModelConvention class:

[!code-csharp]

A route template for TheContactPage/{text?} is added later in this topic. The Contact Page route has a default order of null (Order = 0), so it matches before the {globalTemplate?} route template which has Order = 1.
The {aboutTemplate?} route template is show in the preceding code. The {aboutTemplate?} template is given an Order of 2. When the About page is requested at /About/RouteDataValue, "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["aboutTemplate"] (Order = 2) due to setting the Order property.
The {otherPagesTemplate?} route template is shown in the preceding code. The {otherPagesTemplate?} template is given an Order of 2. When any page in the Pages/OtherPages folder is requested with a route parameter:
For example, /OtherPages/Page1/xyz
The route data value "xyz" is loaded into RouteData.Values["globalTemplate"] (Order = 1).
RouteData.Values["otherPagesTemplate"] with (Order = 2) is not loaded due to the Order property 2 having a higher value.

When possible, don't set the Order. When Order is not set, it defaults to Order = 0. Rely on routing to select the correct route rather than the Order property.

Request the sample's About page at localhost:{port}/About/GlobalRouteValue and inspect the result:

The sample app uses the Rick.Docs.Samples.RouteInfo NuGet package to display routing information in the logging output. Using localhost:{port}/About/GlobalRouteValue, the logger displays the request, the Order, and the template used:

info: SampleApp.Pages.AboutModel[0]
       /About/GlobalRouteValue   Order = 1 Template = About/{globalTemplate?}

Add an app model convention to all pages

Use xref:Microsoft.AspNetCore.Mvc.RazorPages.RazorPagesOptions.Conventions to create and add an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageApplicationModelConvention to the collection of xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageConvention instances that are applied during page app model construction.

To demonstrate this and other conventions later in the topic, the sample app includes an AddHeaderAttribute class. The class constructor accepts a name string and a values string array. These values are used in its OnResultExecuting method to set a response header. The full class is shown in the Page model action conventions section later in the topic.

The sample app uses the AddHeaderAttribute class to add a header, GlobalHeader, to all of the pages in the app:

[!code-csharp]

Program.cs:

[!code-csharp]

Request the sample's About page at localhost:{port}/About and inspect the headers to view the result:

Add a handler model convention to all pages

Use xref:Microsoft.AspNetCore.Mvc.RazorPages.RazorPagesOptions.Conventions to create and add an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageHandlerModelConvention to the collection of xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageConvention instances that are applied during page handler model construction.

[!code-csharp]

Page route action conventions

The default route model provider that derives from xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageRouteModelProvider invokes conventions which are designed to provide extensibility points for configuring page routes.

Folder route model convention

Use xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddFolderRouteModelConvention* to create and add an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageRouteModelConvention that invokes an action on the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageRouteModel for all of the pages under the specified folder.

The sample app uses xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddFolderRouteModelConvention* to add an {otherPagesTemplate?} route template to the pages in the OtherPages folder:

[!code-csharp]

The xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel.Order* property for the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel is set to 2. This ensures that the template for {globalTemplate?} (set earlier in the topic to 1) is given priority for the first route data value position when a single route value is provided. If a page in the Pages/OtherPages folder is requested with a route parameter value (for example, /OtherPages/Page1/RouteDataValue), "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["otherPagesTemplate"] (Order = 2) due to setting the Order property.

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

Request the sample's Page1 page at localhost:5000/OtherPages/Page1/GlobalRouteValue/OtherPagesRouteValue and inspect the result:

Page route model convention

Use xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddPageRouteModelConvention* to create and add an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageRouteModelConvention that invokes an action on the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageRouteModel for the page with the specified name.

The sample app uses AddPageRouteModelConvention to add an {aboutTemplate?} route template to the About page:

[!code-csharp]

The xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel.Order* property for the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel is set to 2. This ensures that the template for {globalTemplate?} (set earlier in the topic to 1) is given priority for the first route data value position when a single route value is provided. If the About page is requested with a route parameter value at /About/RouteDataValue, "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["aboutTemplate"] (Order = 2) due to setting the Order property.

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

Request the sample's About page at localhost:{port}/About/GlobalRouteValue/AboutRouteValue and inspect the result:

The logger output displays:

info: SampleApp.Pages.AboutModel[0]
       /About/GlobalRouteValue/AboutRouteValue   Order = 2 Template = About/{globalTemplate?}/{aboutTemplate?}

Use a parameter transformer to customize page routes

See Parameter transformers.

Configure a page route

Use xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.AddPageRoute* to configure a route to a page at the specified page path. Generated links to the page use the specified route. xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.AddPageRoute%2A uses xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddPageRouteModelConvention%2A to establish the route.

The sample app creates a route to /TheContactPage for the Contact Razor Page:

[!code-csharp]

The Contact page can also be reached at /Contact1` via its default route.

The sample app's custom route to the Contact page allows for an optional text route segment ({text?}). The page also includes this optional segment in its @page directive in case the visitor accesses the page at its /Contact route:

[!code-cshtml]

Note that the URL generated for the Contact link in the rendered page reflects the updated route:

Visit the Contact page at either its ordinary route, /Contact, or the custom route, /TheContactPage. If you supply an additional text route segment, the page shows the HTML-encoded segment that you provide:

Page model action conventions

The default page model provider that implements xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageApplicationModelProvider invokes conventions which are designed to provide extensibility points for configuring page models. These conventions are useful when building and modifying page discovery and processing scenarios.

For the examples in this section, the sample app uses an AddHeaderAttribute class, which is a xref:Microsoft.AspNetCore.Mvc.Filters.ResultFilterAttribute, that applies a response header:

[!code-csharp]

Using conventions, the sample demonstrates how to apply the attribute to all of the pages in a folder and to a single page.

Folder app model convention

Use xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddFolderApplicationModelConvention* to create and add an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageApplicationModelConvention that invokes an action on xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageApplicationModel instances for all pages under the specified folder.

The sample demonstrates the use of AddFolderApplicationModelConvention by adding a header, OtherPagesHeader, to the pages inside the OtherPages folder of the app:

[!code-csharp]

Request the sample's Page1 page at localhost:5000/OtherPages/Page1 and inspect the headers to view the result:

Page app model convention

Use xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.AddPageApplicationModelConvention* to create and add an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageApplicationModelConvention that invokes an action on the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageApplicationModel for the page with the specified name.

The sample demonstrates the use of AddPageApplicationModelConvention by adding a header, AboutHeader, to the About page:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

Configure a filter

xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.ConfigureFilter* configures the specified filter to apply. You can implement a filter class, but the sample app shows how to implement a filter in a lambda expression, which is implemented behind-the-scenes as a factory that returns a filter:

[!code-csharp]

The page app model is used to check the relative path for segments that lead to the Page2 page in the OtherPages folder. If the condition passes, a header is added. If not, the EmptyFilter is applied.

EmptyFilter is an Action filter. Since Action filters are ignored by Razor Pages, the EmptyFilter has no effect as intended if the path doesn't contain OtherPages/Page2.

Request the sample's Page2 page at localhost:5000/OtherPages/Page2 and inspect the headers to view the result:

Configure a filter factory

xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.ConfigureFilter* configures the specified factory to apply filters to all Razor Pages.

The sample app provides an example of using a filter factory by adding a header, FilterFactoryHeader, with two values to the app's pages:

[!code-csharp]

AddHeaderWithFactory.cs:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

MVC Filters and the Page filter (IPageFilter)

MVC Action filters are ignored by Razor Pages, since Razor Pages use handler methods. Other types of MVC filters are available for you to use: Authorization, Exception, Resource, and Result. For more information, see the Filters topic.

The Page filter (xref:Microsoft.AspNetCore.Mvc.Filters.IPageFilter) is a filter that applies to Razor Pages. For more information, see Filter methods for Razor Pages.

Additional resources

:::moniker-end

:::moniker range=">= aspnetcore-3.0 < aspnetcore-6.0"

Learn how to use page route and app model provider conventions to control page routing, discovery, and processing in Razor Pages apps.

When you need to configure custom page routes for individual pages, configure routing to pages with the AddPageRoute convention described later in this topic.

To specify a page route, add route segments, or add parameters to a route, use the page's @page directive. For more information, see Custom routes.

There are reserved words that can't be used as route segments or parameter names. For more information, see Routing: Reserved routing names.

View or download sample code (how to download)

Scenario	The sample demonstrates ...
Model conventions Conventions.Add IPageRouteModelConvention IPageApplicationModelConvention IPageHandlerModelConvention	Add a route template and header to an app's pages.
Page route action conventions AddFolderRouteModelConvention AddPageRouteModelConvention AddPageRoute	Add a route template to pages in a folder and to a single page.
Page model action conventions AddFolderApplicationModelConvention AddPageApplicationModelConvention ConfigureFilter (filter class, lambda expression, or filter factory)	Add a header to pages in a folder, add a header to a single page, and configure a filter factory to add a header to an app's pages.

Razor Pages conventions are configured using an xref:Microsoft.Extensions.DependencyInjection.MvcServiceCollectionExtensions.AddRazorPages%2A overload that configures xref:Microsoft.AspNetCore.Mvc.RazorPages.RazorPagesOptions in Startup.ConfigureServices. The following convention examples are explained later in this topic:

public void ConfigureServices(IServiceCollection services)
{
    services.AddRazorPages(options =>
    {
        options.Conventions.Add( ... );
        options.Conventions.AddFolderRouteModelConvention(
            "/OtherPages", model => { ... });
        options.Conventions.AddPageRouteModelConvention(
            "/About", model => { ... });
        options.Conventions.AddPageRoute(
            "/Contact", "TheContactPage/{text?}");
        options.Conventions.AddFolderApplicationModelConvention(
            "/OtherPages", model => { ... });
        options.Conventions.AddPageApplicationModelConvention(
            "/About", model => { ... });
        options.Conventions.ConfigureFilter(model => { ... });
        options.Conventions.ConfigureFilter( ... );
    });
}

Route order

Routes specify an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel.Order* for processing (route matching).

Order	Behavior
-1	The route is processed before other routes are processed.
0	Order isn't specified (default value). Not assigning `Order` (`Order = null`) defaults the route `Order` to 0 (zero) for processing.
1, 2, … n	Specifies the route processing order.

Route processing is established by convention:

Routes are processed in sequential order (-1, 0, 1, 2, … n).
When routes have the same Order, the most specific route is matched first followed by less specific routes.
When routes with the same Order and the same number of parameters match a request URL, routes are processed in the order that they're added to the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.

Razor Pages routing and MVC controller routing share an implementation. Information on route order in the MVC topics is available at Routing to controller actions: Ordering attribute routes.

Model conventions

Add a delegate for xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageConvention to add model conventions that apply to Razor Pages.

Add a route model convention to all pages

The sample app adds a {globalTemplate?} route template to all of the pages in the app:

[!code-csharp]

A route template for TheContactPage/{text?} is added later in the topic. The Contact Page route has a default order of null (Order = 0), so it matches before the {globalTemplate?} route template.
An {aboutTemplate?} route template is added later in the topic. The {aboutTemplate?} template is given an Order of 2. When the About page is requested at /About/RouteDataValue, "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["aboutTemplate"] (Order = 2) due to setting the Order property.
An {otherPagesTemplate?} route template is added later in the topic. The {otherPagesTemplate?} template is given an Order of 2. When any page in the Pages/OtherPages folder is requested with a route parameter (for example, /OtherPages/Page1/RouteDataValue), "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["otherPagesTemplate"] (Order = 2) due to setting the Order property.

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

[!code-csharp]

Request the sample's About page at localhost:5000/About/GlobalRouteValue and inspect the result:

Add an app model convention to all pages

The sample app uses the AddHeaderAttribute class to add a header, GlobalHeader, to all of the pages in the app:

[!code-csharp]

Startup.cs:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

Add a handler model convention to all pages

[!code-csharp]

Startup.cs:

[!code-csharp]

Page route action conventions

Folder route model convention

[!code-csharp]

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

Request the sample's Page1 page at localhost:5000/OtherPages/Page1/GlobalRouteValue/OtherPagesRouteValue and inspect the result:

Page route model convention

The sample app uses AddPageRouteModelConvention to add an {aboutTemplate?} route template to the About page:

[!code-csharp]

The xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel.Order* property for the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel is set to 2. This ensures that the template for {globalTemplate?} (set earlier in the topic to 1) is given priority for the first route data value position when a single route value is provided. If the About page is requested with a route parameter value at /About/RouteDataValue, "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["aboutTemplate"] (Order = 2) due to setting the Order property.

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

Request the sample's About page at localhost:5000/About/GlobalRouteValue/AboutRouteValue and inspect the result:

Use a parameter transformer to customize page routes

Page routes generated by ASP.NET Core can be customized using a parameter transformer. A parameter transformer implements IOutboundParameterTransformer and transforms the value of parameters. For example, a custom SlugifyParameterTransformer parameter transformer changes the SubscriptionManagement route value to subscription-management.

The PageRouteTransformerConvention page route model convention applies a parameter transformer to the folder and file name segments of automatically generated page routes in an app. For example, the Razor Pages file at /Pages/SubscriptionManagement/ViewAll.cshtml would have its route rewritten from /SubscriptionManagement/ViewAll to /subscription-management/view-all.

PageRouteTransformerConvention only transforms the automatically generated segments of a page route that come from the Razor Pages folder and file name. It doesn't transform route segments added with the @page directive. The convention also doesn't transform routes added by xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.AddPageRoute*.

The PageRouteTransformerConvention is registered as an option in Startup.ConfigureServices:

public void ConfigureServices(IServiceCollection services)
{
    services.AddRazorPages(options =>
    {
        options.Conventions.Add(
            new PageRouteTransformerConvention(
                new SlugifyParameterTransformer()));
    });
}

[!code-csharp]

[!INCLUDE]

Configure a page route

The sample app creates a route to /TheContactPage for Contact.cshtml:

[!code-csharp]

The Contact page can also be reached at /Contact via its default route.

The sample app's custom route to the Contact page allows for an optional text route segment ({text?}). The page also includes this optional segment in its @page directive in case the visitor accesses the page at its /Contact route:

[!code-cshtml]

Note that the URL generated for the Contact link in the rendered page reflects the updated route:

Visit the Contact page at either its ordinary route, /Contact, or the custom route, /TheContactPage. If you supply an additional text route segment, the page shows the HTML-encoded segment that you provide:

Page model action conventions

For the examples in this section, the sample app uses an AddHeaderAttribute class, which is a xref:Microsoft.AspNetCore.Mvc.Filters.ResultFilterAttribute, that applies a response header:

[!code-csharp]

Using conventions, the sample demonstrates how to apply the attribute to all of the pages in a folder and to a single page.

Folder app model convention

The sample demonstrates the use of AddFolderApplicationModelConvention by adding a header, OtherPagesHeader, to the pages inside the OtherPages folder of the app:

[!code-csharp]

Request the sample's Page1 page at localhost:5000/OtherPages/Page1 and inspect the headers to view the result:

Page app model convention

The sample demonstrates the use of AddPageApplicationModelConvention by adding a header, AboutHeader, to the About page:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

Configure a filter

[!code-csharp]

EmptyFilter is an Action filter. Since Action filters are ignored by Razor Pages, the EmptyFilter has no effect as intended if the path doesn't contain OtherPages/Page2.

Request the sample's Page2 page at localhost:5000/OtherPages/Page2 and inspect the headers to view the result:

Configure a filter factory

xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.ConfigureFilter* configures the specified factory to apply filters to all Razor Pages.

The sample app provides an example of using a filter factory by adding a header, FilterFactoryHeader, with two values to the app's pages:

[!code-csharp]

AddHeaderWithFactory.cs:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

MVC Filters and the Page filter (IPageFilter)

The Page filter (xref:Microsoft.AspNetCore.Mvc.Filters.IPageFilter) is a filter that applies to Razor Pages. For more information, see Filter methods for Razor Pages.

Additional resources

:::moniker-end

:::moniker range="< aspnetcore-2.2"

Learn how to use page route and app model provider conventions to control page routing, discovery, and processing in Razor Pages apps.

When you need to configure custom page routes for individual pages, configure routing to pages with the AddPageRoute convention described later in this topic.

To specify a page route, add route segments, or add parameters to a route, use the page's @page directive. For more information, see Custom routes.

There are reserved words that can't be used as route segments or parameter names. For more information, see Routing: Reserved routing names.

View or download sample code (how to download)

Scenario	The sample demonstrates ...
Model conventions Conventions.Add IPageRouteModelConvention IPageApplicationModelConvention IPageHandlerModelConvention	Add a route template and header to an app's pages.
Page route action conventions AddFolderRouteModelConvention AddPageRouteModelConvention AddPageRoute	Add a route template to pages in a folder and to a single page.
Page model action conventions AddFolderApplicationModelConvention AddPageApplicationModelConvention ConfigureFilter (filter class, lambda expression, or filter factory)	Add a header to pages in a folder, add a header to a single page, and configure a filter factory to add a header to an app's pages.

Razor Pages conventions are added and configured using the xref:Microsoft.Extensions.DependencyInjection.MvcRazorPagesMvcBuilderExtensions.AddRazorPagesOptions* extension method to xref:Microsoft.Extensions.DependencyInjection.MvcServiceCollectionExtensions.AddMvc* on the service collection in the Startup class. The following convention examples are explained later in this topic:

public void ConfigureServices(IServiceCollection services)
{
    services.AddMvc()
        .AddRazorPagesOptions(options =>
        {
            options.Conventions.Add( ... );
            options.Conventions.AddFolderRouteModelConvention(
                "/OtherPages", model => { ... });
            options.Conventions.AddPageRouteModelConvention(
                "/About", model => { ... });
            options.Conventions.AddPageRoute(
                "/Contact", "TheContactPage/{text?}");
            options.Conventions.AddFolderApplicationModelConvention(
                "/OtherPages", model => { ... });
            options.Conventions.AddPageApplicationModelConvention(
                "/About", model => { ... });
            options.Conventions.ConfigureFilter(model => { ... });
            options.Conventions.ConfigureFilter( ... );
        });
}

Route order

Routes specify an xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel.Order* for processing (route matching).

Order	Behavior
-1	The route is processed before other routes are processed.
0	Order isn't specified (default value). Not assigning `Order` (`Order = null`) defaults the route `Order` to 0 (zero) for processing.
1, 2, … n	Specifies the route processing order.

Route processing is established by convention:

Routes are processed in sequential order (-1, 0, 1, 2, … n).
When routes have the same Order, the most specific route is matched first followed by less specific routes.
When routes with the same Order and the same number of parameters match a request URL, routes are processed in the order that they're added to the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.PageConventionCollection.

Razor Pages routing and MVC controller routing share an implementation. Information on route order in the MVC topics is available at Routing to controller actions: Ordering attribute routes.

Model conventions

Add a delegate for xref:Microsoft.AspNetCore.Mvc.ApplicationModels.IPageConvention to add model conventions that apply to Razor Pages.

Add a route model convention to all pages

The sample app adds a {globalTemplate?} route template to all of the pages in the app:

[!code-csharp]

A route template for TheContactPage/{text?} is added later in the topic. The Contact Page route has a default order of null (Order = 0), so it matches before the {globalTemplate?} route template.
An {aboutTemplate?} route template is added later in the topic. The {aboutTemplate?} template is given an Order of 2. When the About page is requested at /About/RouteDataValue, "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["aboutTemplate"] (Order = 2) due to setting the Order property.
An {otherPagesTemplate?} route template is added later in the topic. The {otherPagesTemplate?} template is given an Order of 2. When any page in the Pages/OtherPages folder is requested with a route parameter (for example, /OtherPages/Page1/RouteDataValue), "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["otherPagesTemplate"] (Order = 2) due to setting the Order property.

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

Razor Pages options, such as adding xref:Microsoft.AspNetCore.Mvc.RazorPages.RazorPagesOptions.Conventions, are added when MVC is added to the service collection in Startup.ConfigureServices. For an example, see the sample app.

[!code-csharp]

Request the sample's About page at localhost:5000/About/GlobalRouteValue and inspect the result:

Add an app model convention to all pages

The sample app uses the AddHeaderAttribute class to add a header, GlobalHeader, to all of the pages in the app:

[!code-csharp]

Startup.cs:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

Add a handler model convention to all pages

[!code-csharp]

Startup.cs:

[!code-csharp]

Page route action conventions

Folder route model convention

[!code-csharp]

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

Request the sample's Page1 page at localhost:5000/OtherPages/Page1/GlobalRouteValue/OtherPagesRouteValue and inspect the result:

Page route model convention

The sample app uses AddPageRouteModelConvention to add an {aboutTemplate?} route template to the About page:

[!code-csharp]

The xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel.Order* property for the xref:Microsoft.AspNetCore.Mvc.ApplicationModels.AttributeRouteModel is set to 2. This ensures that the template for {globalTemplate?} (set earlier in the topic to 1) is given priority for the first route data value position when a single route value is provided. If the About page is requested with a route parameter value at /About/RouteDataValue, "RouteDataValue" is loaded into RouteData.Values["globalTemplate"] (Order = 1) and not RouteData.Values["aboutTemplate"] (Order = 2) due to setting the Order property.

Wherever possible, don't set the Order, which results in Order = 0. Rely on routing to select the correct route.

Request the sample's About page at localhost:5000/About/GlobalRouteValue/AboutRouteValue and inspect the result:

Configure a page route

The sample app creates a route to /TheContactPage for Contact.cshtml:

[!code-csharp]

The Contact page can also be reached at /Contact via its default route.

[!code-cshtml]

Note that the URL generated for the Contact link in the rendered page reflects the updated route:

Page model action conventions

For the examples in this section, the sample app uses an AddHeaderAttribute class, which is a xref:Microsoft.AspNetCore.Mvc.Filters.ResultFilterAttribute, that applies a response header:

[!code-csharp]

Using conventions, the sample demonstrates how to apply the attribute to all of the pages in a folder and to a single page.

Folder app model convention

The sample demonstrates the use of AddFolderApplicationModelConvention by adding a header, OtherPagesHeader, to the pages inside the OtherPages folder of the app:

[!code-csharp]

Request the sample's Page1 page at localhost:5000/OtherPages/Page1 and inspect the headers to view the result:

Page app model convention

The sample demonstrates the use of AddPageApplicationModelConvention by adding a header, AboutHeader, to the About page:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

Configure a filter

[!code-csharp]

EmptyFilter is an Action filter. Since Action filters are ignored by Razor Pages, the EmptyFilter has no effect as intended if the path doesn't contain OtherPages/Page2.

Request the sample's Page2 page at localhost:5000/OtherPages/Page2 and inspect the headers to view the result:

Configure a filter factory

xref:Microsoft.Extensions.DependencyInjection.PageConventionCollectionExtensions.ConfigureFilter* configures the specified factory to apply filters to all Razor Pages.

The sample app provides an example of using a filter factory by adding a header, FilterFactoryHeader, with two values to the app's pages:

[!code-csharp]

AddHeaderWithFactory.cs:

[!code-csharp]

Request the sample's About page at localhost:5000/About and inspect the headers to view the result:

MVC Filters and the Page filter (IPageFilter)

The Page filter (xref:Microsoft.AspNetCore.Mvc.Filters.IPageFilter) is a filter that applies to Razor Pages. For more information, see Filter methods for Razor Pages.

Additional resources

:::moniker-end

66 KiB Raw Blame History

Razor Pages route and app conventions in ASP.NET Core

Route order

Model conventions

Add a route model convention to all pages

Add an app model convention to all pages

Add a handler model convention to all pages

Page route action conventions

Folder route model convention

Page route model convention

Use a parameter transformer to customize page routes

Configure a page route

Page model action conventions

MVC Filters and the Page filter (IPageFilter)

Additional resources

Route order

Model conventions

Add a route model convention to all pages

Add an app model convention to all pages

Add a handler model convention to all pages

Page route action conventions

Folder route model convention

Page route model convention

Use a parameter transformer to customize page routes

Configure a page route

Page model action conventions

MVC Filters and the Page filter (IPageFilter)

Additional resources

Route order

Model conventions

Add a route model convention to all pages

Add an app model convention to all pages

Add a handler model convention to all pages

Page route action conventions

Folder route model convention

Page route model convention

Configure a page route

Page model action conventions

MVC Filters and the Page filter (IPageFilter)

Additional resources

66 KiB

Raw Blame History