Blazor WebAssembly Shared UI Library

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

Adding a project reference from a Blazor WebAssembly project to a Razor Class Library produces NETSDK1082 There was no runtime pack for Microsoft.AspNetCore.App available for the specified RuntimeIdentifier 'browser-wasm'.

Expected Behavior

Use case: I wish to store my UI and logic in a shared class library that can be accessed by both a Blazor WASM app and a Blazor MAUI app, so I create a Razor Class Library to hold this logic.

I would expect that you would be able to reference a Razor Class Library from a Blazor WebAssembly application.

Steps To Reproduce

A demonstration solution is available here: https://github.com/Foxtrek64/BlazorSharedUI This solution contains three projects:

• A Maui Blazor app built from the default .NET 7 template, unmodified.
• A Razor Class Library. I’ve deleted the default Areas directory, added a Pages directory, and copied in the Index.razor file from the Blazor WebAssembly application.
• A Blazor WebAssembly application built with the Empty template, with Linux Docker support and PWA support.

Building the Blazor WebAssembly app and running it results in exactly what you might expect - the browser opens and shows Hello World as described by the default Index.razor file.

Steps to reproduce:

1. Right click on BlazorSharedUI.Web -> Add -> Project Reference…
2. Add a reference to BlazorSharedUI.Shared
3. Click OK
4. Run the app again. The NETSDK1082 exception is thrown at build.

The Maui Blazor app is not required for this demo, but I added it for completeness. Ideally, both of these projects would reference the .Shared library and pull their UI from there, but I can’t even get them to reference the library without catching on fire.

Exceptions (if any)

No response

.NET Version

7.0.100

Anything else?

There are many suggestions out there, such as #27738, suggest changing the project SDK of the shared project from Microsoft.NET.Sdk.Razor to Microsoft.NET.Sdk. Making this change simply produces a second error and has a tangential effect of no longer recognizing the wwwroot folder if one is present in the project (icon changes from a globe to the standard folder icon):

MSB4057 The target "RazorGenerateComponentDesignTime" does not exist in the project.

[mkArtakMSFT]

Thanks for contacting us. Looks like you’ve checked the Support pages and views option when you were creating the Razor Class Library project. Referencing these projects from a Blazor WebAssembly project is not supported. consider creating the project without that flag checked: https://github.com/Foxtrek64/BlazorSharedUI/blob/f98f2cce9b9413dc8e473df217492ba27c6f9c81/BlazorSharedUI.Shared/BlazorSharedUI.Shared.csproj#L7

[andrewaggb]

So to be clear - Is the current state of things that I can’t share a Page in an RCL library between wasm and server? I can share static content and components but not pages?