Aspnetcore: Missing references in Blazor components latest 16.4.0

[vsfeedback]

_This issue has been moved from a ticket on Developer Community._

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[regression] [worked-in:Latest stable release before 16.4.0]
After upgrading to latest 16.4.0 some Blazor components ar marked as missing. The project still compiles fine, so it seems to be a VisualStudio issue.
Also, the issue dissapears if I open the blazor component .razor file to edit... it seems that when its opened the references appears again.

I attach 2 screenshots showing how when I open the blazor component files, the references appear, and they're missing when the files are not being edited.

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Original Comments

Visual Studio Feedback System on 12/3/2019, 11:57 PM:

We have directed your feedback to the appropriate engineering team for further evaluation. The team will review the feedback and notify you about the next steps.

charlesdeluxe on 12/7/2019, 02:51 PM:

(private comment, text removed)

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Original Solutions

(no solutions)

[mkArtakMSFT]

Thanks for contacting us.
@NTaylorMullen do you know what could have caused this? Do we need a repro project to investigate this?

[VaclavElias]

I also have the same problem. Project compiles and runs ok. Just the red squiggles. Visual Studio 16.4.1, .NET Core 3.1. Components are local in the same folder.

[NTaylorMullen]

@NTaylorMullen do you know what could have caused this? Do we need a repro project to investigate this?

A repro project wouldn't help much with this.

@VaclavElias what's the output of your dotnet --info?

[VaclavElias]

.NET Core SDK (reflecting any global.json):
Version: 3.1.100
Commit: cd82f021f4

Runtime Environment:
OS Name: Windows
OS Version: 10.0.18363
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\3.1.100\

Host (useful for support):
Version: 3.1.0
Commit: 65f04fb6db

.NET Core SDKs installed:
1.1.13 [C:\Program Files\dotnet\sdk]
2.1.602 [C:\Program Files\dotnet\sdk]
2.1.604 [C:\Program Files\dotnet\sdk]
2.1.700 [C:\Program Files\dotnet\sdk]
2.1.701 [C:\Program Files\dotnet\sdk]
2.1.801 [C:\Program Files\dotnet\sdk]
2.1.802 [C:\Program Files\dotnet\sdk]
2.2.202 [C:\Program Files\dotnet\sdk]
2.2.203 [C:\Program Files\dotnet\sdk]
2.2.204 [C:\Program Files\dotnet\sdk]
2.2.300 [C:\Program Files\dotnet\sdk]
2.2.301 [C:\Program Files\dotnet\sdk]
2.2.401 [C:\Program Files\dotnet\sdk]
2.2.402 [C:\Program Files\dotnet\sdk]
3.0.100-preview6-012264 [C:\Program Files\dotnet\sdk]
3.1.100 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
Microsoft.AspNetCore.All 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.1.14 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.2.3 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.2.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.2.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.2.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.2.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.All 2.2.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.12 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.1.14 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.2.3 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.2.4 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.2.5 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.2.6 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.2.7 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 2.2.8 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.0.0-preview6.19307.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 1.0.15 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 1.1.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.9 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.11 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.13 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.1.14 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.2.3 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.2.4 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.2.5 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.2.6 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.2.7 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 2.2.8 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.0.0-preview6-27804-01 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

[NTaylorMullen]

Hmm @VaclavElias that's what i'd expect. If you're up for a nuclear option to verify something would you mind trying uninstalling Visual Studio and then re-installing it?

[VaclavElias]

I won't be able to do this at the moment because of my time restriction but if I save some time I might try it on another 2 computers where I also run Visual Studio.

[chrdlx]

I'm the one who reported this in VS Feedback.
I uninstalled/installed VS several times, in my personal computer & my work computer, with different combinations of 3.0.0 and 3.1.0 without success. I also tried deleting manually the sdk & runtime folders. Resetting VS settings to default.

C:Users\Chr>dotnet --info
.NET Core SDK (reflecting any global.json):
Version: 3.1.100
Commit: cd82f021f4

Runtime Environment:
OS Name: Windows
OS Version: 10.0.18363
OS Platform: Windows
RID: win10-x64
Base Path: C:\Program Files\dotnet\sdk\3.1.100\

Host (useful for support):
Version: 3.1.0
Commit: 65f04fb6db

.NET Core SDKs installed:
3.1.100 [C:\Program Files\dotnet\sdk]

.NET Core runtimes installed:
Microsoft.AspNetCore.All 2.1.14 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.All]
Microsoft.AspNetCore.App 2.1.14 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 2.1.14 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 3.1.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

[chrdlx]

This .gif shows how components are recognized or not depending on when the component is open for edit.
When I close the components edit windows, the references start to dissapear. Even the namespace is not recognized.

Regards!

[NTaylorMullen]

So odd. I can't reproduce this at all.

• Do you see the same behavior with the default Blazor template? Aka if you create a new project, open up Index.razor and try using the Counter component does it work as you'd expect?
• What workloads do you have checked in your Visual Studio installation?
• Do you happen to have any notable VS extensions installed?

[chrdlx]

@NTaylorMullen
No, I don't see the same behavior in the default template, it seems that at some point, while the folder structure grows, it starts happening.... I couldn't pinpoint why, I even started removing folders one by one in my project until it works ok, but couldn't find out why.
I can send you a VS project where it happens, do you have an email so I can send it to you?

Regards

[NTaylorMullen]

No, I don't see the same behavior in the default template, it seems that at some point, while the folder structure grows, it starts happening.... I couldn't pinpoint why, I even started removing folders one by one in my project until it works ok, but couldn't find out why.

Ah, definitely interesting.

I can send you a VS project where it happens, do you have an email so I can send it to you?

Hmm to not paste my email over the interwebs would it be possible for you to create a private GitHub repo (free now) and give me access that way? I can also send you the email address privately via twitter if that works too. Thanks again for the flexibility here 😄

[chrdlx]

@NTaylorMullen I tried to contact you at twitter but there's no answer, I prefer to just send you a .zip file if possible!

[NTaylorMullen]

@NTaylorMullen I tried to contact you at twitter but there's no answer, I prefer to just send you a .zip file if possible!

Just responded, looks like Twitter was bad and didn't notify me of your tweet 😄

[ChiMonLam1979]

Having the same issue here - did this get solved? :)

[ScottyBlazor]

I also get this issues, if I open the code window for the component the squiggles go away, but reappear when I close the component code window.

trying to add a using statement to the .razor code using my component, won't even list the folder my component is in until I open the component code window.
and also has the same issue in code for the page.

[nguyenlamlll]

I got (somewhat) the same problem as well. References to Blazor components are really buggy. It just worked a few min ago, then it was gone.

In Visual Studio 2019 v16.5.1:

I have a component in a folder Components, specifying @namespace RandomEnglishExercises.Components at the top:

When I use the component, the IDE seems to notice the existence of the component. However, when I build, it fails.

On other tests, without @namespace ..., still cannot work.
Using the component's full name does not work as well.

My SDK version is 3.1.3.

[chrdlx]

It seems that with the latest VS 16.6.0, this issue has been corrected.
Has anyone else had this experience too?

[mkArtakMSFT]

@NTaylorMullen should this be closed now?

[NTaylorMullen]

Yup, this should be fully fixed in the upcoming 16.7-Preview3 Visual Studio release.