问题
I have a beginner ASP.NET Core project in Visual Studio 2017, and I am at the scaffolding step of the HelloWorld. The Scaffolding does not work, I tested on a first computer, then at a second one...
when I try to generate a controller with views , it gives the following error on the first machine:
Microsoft Visual Studio
Error
There was an error running the selected code generator:
'Unhandled Exception: System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.VisualStudio.Web.CodeGeneration.Utils, Version=1.1.1.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified. at Microsoft.VisualStudio.Web.CodeGeneration.Design.Program.Main(String[] args)'
OK
On the second machine:
Microsoft Visual Studio
Error
There was an error running the selected code generator:
'Error: assembly specified in the dependencies manifest was not found -- package: 'microsoft.applicationinsights.aspnetcore', version: '2.1.0', path: 'lib/netstandard1.6/Microsoft.ApplicationInsights.AspNetCore.dll''
OK
回答1:
The following works for me.
I deleted bin & obj folders, build the project again and it works.
In case if it gives you error: it couldn't find project.deps.json in debug folder.
Set project to debug, ran it and now you can add scaffolded items.
回答2:
Clear local NuGet cache with the command from console:
dotnet nuget locals all --clear
Restore all Packages
Install (or update) NuGet package Microsoft.CodeAnalysis.CSharp.Workspaces version 2.0.0 (or higher) EDIT: It seams versions 2.3.0 and 2.3.1 cause some problems. So stick with 2.2.0 at most until MS solves this issues (https://github.com/dotnet/roslyn/issues/20873).
Restore all Packages again and try scaffolding.
That worked for me.
Be sure you have properly referenced these packages in your project:
<PackageReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Design" Version="1.1.1" />
<DotNetCliToolReference Include="Microsoft.VisualStudio.Web.CodeGeneration.Tools" Version="1.0.1" />
My projects uses Asp.Net Core 1.1.2 and VS2017 Community
回答3:
I has the same situation. On .net core version 2.2 and with VS 2017 Enterprise.
The next instruction hepls for me:
- open VS with Admin rights.
- load solution to VS
- add controller from scaffolding menu. VS will install 'Microsoft.VisualStudio.Web.CodeGeneration.Design' and 'Microsoft.VisualStudio.Web.CodeGeneration.Tools' packages.
- close VS
- open VS and load project. Add controllers via scaffloading is working fine
Maybe this instruction helps somebody, Thanks.
回答4:
For the benefit of searchers:
I got this in VS2019. The cause was that my code was broken.
Didn't realise why to start, but when you realise that code generation is a nuget package; if the project doesn't build, then Visual Studio can't get to that package.
Once I got the code compiling, this error went away.
回答5:
you should change the version of Microsoft.VisualStudio.Web.CodeGeneration.Design exactly like the version of Microsoft.AspNetCore.App
回答6:
I was trying to run the command bellow with the version 3.0.0 of asp.net core installed, so I got the same error Command: dotnet aspnet-codegenerator controller -name MoviesController -m Movie -dc MvcMovieContext --relativeFolderPath Controllers --useDefaultLayout --referenceScriptLibraries
Error: Scaffolding failed. Could not load file or assembly 'Microsoft.VisualStudio.Web.CodeGeneration, Version=3.0.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified.
- Solution:
dotnet nuget locals all --clear
dotnet remove package Microsoft.VisualStudio.Web.CodeGeneration.Utils
Change the PackageRefere for the version 2.2.0
Run the command again. dotnet aspnet-codegenerator controller -name MoviesController -m Movie -dc MvcMovieContext --relativeFolderPath Controllers --useDefaultLayout --referenceScriptLibraries
回答7:
Solution:
- Go to VS2019 --> Dependencies -->Packages
- Click on Manage NuGet
- In the search type "Microsoft.VisualStudio.Web.CodeGeneration.Utils" or the Dll that is missing.
- Click Install.
- Rebuild the solution
- Then add the Scaffolding item. It works..:-)
来源：https://stackoverflow.com/questions/45139243/asp-net-core-scaffolding-does-not-work-in-vs-2017