Nswag: GetExportedTypes: Method does not have an implementation

[molszews]

What could be the reason for following errors:

1>  Unhandled Exception: System.TypeLoadException: Method 'Negotiate' in type 'Api.JsonContentNegotiator' from assembly 'Api, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' does not have an implementation.
1>     at System.Reflection.RuntimeAssembly.GetExportedTypes(RuntimeAssembly assembly, ObjectHandleOnStack retTypes)
1>     at System.Reflection.RuntimeAssembly.GetExportedTypes()
1>     at System.Reflection.Assembly.get_ExportedTypes()
1>     at NSwag.SwaggerGeneration.WebApi.WebApiToSwaggerGenerator.GetControllerClasses(Assembly assembly)
1>     at Program.Main(String[] args)

Of course the method is implemented and the Api project builds correctly.
I think I had same issue once, and I had to do some cleanup with dlls then, however I am not able to fix this today. What could be the root cause of presented issue?

[molszews]

It seems that generator and api.dll were referencing different version of the same assembly (net.http or net.http.formatting). Downgrading one used by api.dll solved the issue.

[RicoSuter]

Once i had the same problem in a project. Cant this also be fixed with binding redirects?

[eakoning]

Adding

<dependentAssembly>
        <assemblyIdentity name="System.Net.Http" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.2.0.0" newVersion="4.0.0.0" />
      </dependentAssembly>

to the Web.config solved this problem.

[RicoSuter]

Thanks for reporting here.