Adding Blazor Identity to existing Blazer project fails with a 'null path' exception

kodo65 0

Hi!

I have the following:

.Net SDK 9
Visual Studio Community 2022 v 17.12.3
Windows v10.0.19044
Blazer Server App

When I try to add the Blazor Identity "scaffolding" I get a "There was an error running the selected code generator: 'Value cannot be null. (Parameter 'path'). I can see that some of the EF-framework assemblies and SQLite-engine was installed but nothing else. Is there a solution to this?

Cheers

Tiny Wang-MSFT 2,981 Reputation points Microsoft Vendor

2024-12-18T12:43:11.2466667+00:00

Hi kodu, per my knowledge, Blazor Server App exists in .Net version before .Net 8, so that .Net 9 doesn't have Blazor Server App, may I know whether Blazor Server here mean Blazor web app which is a new template from .Net 8?
kodo65 0 Reputation points

2024-12-18T13:03:48.1633333+00:00

I'm using Blazor web app - sorry for the confusion.
Tianyu Sun-MSFT 31,961 Reputation points Microsoft Vendor

2024-12-18T13:43:50.2+00:00

Hi @kodo65,

I tested with Blazor web app, .NET 9 and VS 2022 v17.12.3, but I failed to reproduce this issue.

I show you the steps I followed, kindly let me know if I missed some steps when I tried to reproduce this issue.

Create a .NET 9 Blazor web app, right-click it => Add => New Scaffolded Item... => pick Blazor Identity => click Add, select DbContext class(I added a new data context type), select Database provider(SQL Server) => click Add.

BTW, if you can share us the complete steps to reproduce this issue and check further, it will be very helpful.

I also find a similar thread(state: "Fixed - pending release"): Scaffolding Identity to a web project fails to complete with an error message of "Value cannot be null. (Parameter 'objectToConvert')". Maybe, it's not the same issue, but once the next version of VS 2022 has been released, I think you can also try to update VS 2022 to the latest version.
Tianyu Sun-MSFT 31,961 Reputation points Microsoft Vendor

2024-12-25T08:20:56.4333333+00:00

@kodo65 ,

Do you still meet this issue? If a repair(VS) doesn't work, perhaps you can try to reinstall the "ASP.NET and web development" workload.

Besides, will it work if you run VS as administrator?

1 answer

kodo65 0 Reputation points

2024-12-18T14:07:56.0233333+00:00

I performed exactly the same steps as you with the exception I selected SQLite as I want this to be a bundled solution without relying on the SQLServer (Windows) service. The target system will be run on Linux which means I need to keep the dependencies in Windows components to a minimum. I thought that relying on SQLite would make my solution "more cross platform". Is this correct?
Please sign in to rate this answer.
Bruce (SqlWork.com) 68,716 Reputation points

2024-12-18T17:13:07.4633333+00:00

as SQLite is an in process database, it will not work on a webfarm, just single sever.

note: I added Blazor identity with sqlite with no issues:

Microsoft Visual Studio Professional 2022 (64-bit) - Preview Version 17.13.0 Preview 2.0

kodo65 0 Reputation points

2024-12-19T07:48:58.23+00:00

Hi!

In-process is no problem to me as I'll run my app as a docker compose stack on Linux. It's encouraging to hear you didn't experience any problems using the identity scaffolding - unfortunately it doesn't work for me though. Maybe the problem is that I use community version and not a preview...?

Cheers

Tianyu Sun-MSFT 31,961 Reputation points Microsoft Vendor

2024-12-20T06:16:12.78+00:00

Hi @kodo65 ,

I'm using Community version as well, I also fail to reproduce this issue.

May I confirm, if you added the Blazor Identity to an existing Blazor project or, a newly created Blazor project without modifying anything?

If it's an existing Blazor project, will it work if you delete the bin, obj and the hidden .vs folder in your project/solution folder?

If it's a newly created Blazor project, will it work if you repair VS(VS Installer => More => Repair)?
Sign in to comment

Use comments to ask for clarification, additional information, or improvements to the question.

Share via

Adding Blazor Identity to existing Blazer project fails with a 'null path' exception

1 answer

Your answer