Skip to main content

ASP.NET Core - Could not load type 'Microsoft.AspNetCore.Mvc.MvcJsonOptions'

After upgrading some packages in an ASP.NET Core application, I got the following error message when I tried to run the application:

System.TypeLoadException: Could not load type 'Microsoft.AspNetCore.Mvc.MvcJsonOptions' from assembly 'Microsoft.AspNetCore.Mvc.Formatters.Json, Version=3.1.20.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'.

   at System.Signature.GetSignature(Void* pCorSig, Int32 cCorSig, RuntimeFieldHandleInternal fieldHandle, IRuntimeMethodInfo methodHandle, RuntimeType declaringType)

   at System.Reflection.RuntimeConstructorInfo.get_Signature()

   at System.Reflection.RuntimeConstructorInfo.GetParametersNoCopy()

   at System.Reflection.RuntimeConstructorInfo.GetParameters()

   at Microsoft.Extensions.Internal.ActivatorUtilities.CreateInstance(IServiceProvider provider, Type instanceType, Object[] parameters)

   at Microsoft.AspNetCore.Builder.UseMiddlewareExtensions.<>c__DisplayClass4_0.<UseMiddleware>b__0(RequestDelegate next)

   at Microsoft.AspNetCore.Builder.ApplicationBuilder.Build()

   at Microsoft.AspNetCore.Hosting.GenericWebHostService.StartAsync(CancellationToken cancellationToken)

This issue was caused because I was using a newer Microsoft.AspNetCore.Mvc package together with an older Swashbuckle package. To solve the problem I had to update Swagger to version 5:

<PackageReference Include="Swashbuckle.AspNetCore" Version="5.0.0" />
That’s it!
Labels:

Popular posts from this blog

Podman– Command execution failed with exit code 125

After updating WSL on one of the developer machines, Podman failed to work. When we took a look through Podman Desktop, we noticed that Podman had stopped running and returned the following error message: Error: Command execution failed with exit code 125 Here are the steps we tried to fix the issue: We started by running podman info to get some extra details on what could be wrong: >podman info OS: windows/amd64 provider: wsl version: 5.3.1 Cannot connect to Podman. Please verify your connection to the Linux system using `podman system connection list`, or try `podman machine init` and `podman machine start` to manage a new Linux VM Error: unable to connect to Podman socket: failed to connect: dial tcp 127.0.0.1:2655: connectex: No connection could be made because the target machine actively refused it. That makes sense as the podman VM was not running. Let’s check the VM: >podman machine list NAME         ...
Read more

Azure DevOps/ GitHub emoji

I’m really bad at remembering emoji’s. So here is cheat sheet with all emoji’s that can be used in tools that support the github emoji markdown markup: All credits go to rcaviers who created this list.
Read more

Cleaner switch expressions with pattern matching in C#

Ever find yourself mapping multiple string values to the same result? Being a C# developer for a long time, I sometimes forget that the C# has evolved so I still dare to chain case labels or reach for a dictionary. Of course with pattern matching this is no longer necessary. With pattern matching, you can express things inline, declaratively, and with zero repetition. A small example I was working on a small script that should invoke different actions depending on the environment. As our developers were using different variations for the same environment e.g.  "tst" alongside "test" , "prd" alongside "prod" .  We asked to streamline this a long time ago, but as these things happen, we still see variations in the wild. This brought me to the following code that is a perfect example for pattern matching: The or keyword here is a logical pattern combinator , not a boolean operator. It matches if either of the specified pattern...
Read more