Aspnetcore: ENC1003 C# Changes made in project will not be applied while the application is running

[jez9999]

Every time I create a brand new ASP.NET Core 3.0 MVC application project, even if I make no changes, when I his F5 and debug the project I get this error for every C# file:

This seems like a bug because it's a pointless warning cluttering up the warnings window. There appears to be no way to get rid of it (because it appears at runtime, I can't even suppress it using the "Suppress warnings" box in the project properties).

[pranavkm]

@tmat \ @jaredpar would you know what could be causing this? I can see this when trying to run any ASP.NET Core Web Application using 3.0-preview8 + VS 16.3 Preview 2. More interestingly, this message pops up any time I edit a vanilla console application:

Is this expected?

[jaredpar]

@jasonmalinowski for IDE routing.

[jasonmalinowski]

@jez9999 The warning is saying that you've made edits while the program is running, but until the program is paused and resumed that edit won't be applied. It used to be that edits were entirely blocked if the program was running; this was weakened to allow the edits but they just can't be applied until the program pauses. The warning would go away once you've stopped debugging. Is that what you're seeing?

[jez9999]

No - I get the warnings immediately upon hitting F5, with no edits being made.

[jasonmalinowski]

OK, got it. @pranavkm's video isn't showing what you're seeing then.

[pranavkm]

@jasonmalinowski yup. I was pointing out yet another scenario where it shows up. But as @jez9999 points out, for ASP.NET Core Web applications, the warning pops up as soon as you start debugging.

[pranavkm]

@jasonmalinowski any idea what might trigger the warning @jez9999 is seeing? Should this issue be tracked elsewhere?

[jasonmalinowski]

@pranavkm: no idea. @tmat will be able to assist further.

[pranavkm]

@tmat is there any thing you need to diagnose this further?

[dotnetshadow]

I'm getting similar issues with my asp.net core 3.0 preview 9 application on visual studio 2019 preview 3

When I ran it as IISExpress I had the issue, so I decided to delete my .vs folder, bin and obj directories. This seemed to fix the issue, it still shows up the very first time, but after that I am able to debug.

When I try to debug using the kestrel, I get the stubborn error and the above solution doesn't fix this issue.

The following shows upon pressing F5

Ironically run dotnet watch run, then go to visual studio and choose Debug->Attach process then it debugs fine

Issue seems to be similar to these:
https://developercommunity.visualstudio.com/content/problem/478768/wrongly-getting-message-edits-were-made-to-the-cod.html

https://developercommunity.visualstudio.com/content/problem/439396/aspnet-core-mvc-edits-were-made-to-the-code-which.html

[pranavkm]

This is resolved in 16.4 release of Visual Studio. See https://github.com/dotnet/roslyn/pull/38501.

[karimh93]

I have the same problem like @jez9999 . Did someone manage how this can be solved?

[tig]

@karimh93 - It doesn't fix the fundamental bug which is that the warning is generated in the first place, but you can create a GlobalSuppressions.cs file at the project root, and add the line:

[assembly: System.Diagnostics.CodeAnalysis.SuppressMessage(null, "ENC1003")]

This will suppress the error and let you debug.

[Alex-Horlock]

If you are like me and you've got here from updating to .Net Core 3.0 and are wondering why you now can't recompile your razor pages on the fly, the solution is that it is now a Nuget package and is explained here:
https://stackoverflow.com/questions/54600273/net-core-3-0-preview-2-razor-views-dont-automatically-recompile-on-change

[LConrade]

I only recently (the last several days) started receving these warning messages after never having received them previously. I have just realised that in the Error List pane, if I change the setting "Build + Intellisense" to just "Build" then I no longer receive these messages, neither in the Error List pane, nor associated with items in Solution Explorer. I must have inadvertently changed that setting without realising. Of course, it means that I no longer receive any other Intellisense-related error notifications but for most of the time I'm not needing to see them. Not sure if that helps others. I think that perhaps this may actually be working as originally designed, though others may think differently. Hope this helps.

[tmat]

@LConrade These warnings are new in 16.3. They are supposed to be displayed only in files that support Edit and Continue. Displaying them in other files was not intentional and has been fixed in 16.4.

[LConrade]

@tmat Terrific. Thanks for the clarification.