Examples given don't work with .netstandard2.0

[schmik]

As far as I can tell, the given example for "Parameterless" won't work with a class lib targeting .Net Standard 2.0 -- which should be a viable target, as Microsoft.Extensions.DependencyInjection itself targets netstandard2.0? IServiceCollection has no method .AddOptions<T>

using Microsoft.Extensions.DependencyInjection;

namespace ExampleLibrary.Extensions.DependencyInjection
{
    public static class ServiceCollectionExtensions
    {
        public static IServiceCollection AddMyLibraryService(
            this IServiceCollection services)
        {
            services.AddOptions<LibraryOptions>()
                .Configure(options =>
                {
                    // Specify default option values
                });

            // Register lib services here...
            // services.AddScoped<ILibraryService, DefaultLibraryService>();

            return services;
        }
    }
}

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Document Details

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• ID: 03494bb6-433a-5385-b664-7b830c37f9ce
• Version Independent ID: d0e9398d-50c6-01b8-a242-4edc8b27df31
• Content: Options pattern guidance for .NET library authors
• Content Source: docs/core/extensions/options-library-authors.md
• Product: dotnet-fundamentals
• GitHub Login: @IEvangelist
• Microsoft Alias: dapine

[IEvangelist]

Hi @schmik - thank you for posting this issue. The AddOptions extension method exists with multiple target framework monikers (TFMs):

• netcoreapp2.1 - .NET Core 2.1
• netcoreapp3.0 - .NET Core 3.0
• netcoreapp3.1 - .NET Core 3.1
• net461 - .NET Framework 4.6.1
• netstandard2.0 - .NET Standard 2.0
• netstandard2.1 - .NET Standard 2.1
• net5.0 - .NET 5.0
• net6 - Previews 1 - 5

The API reference docs show the platforms where this is applicable (expand Applies to):
https://docs.microsoft.com/dotnet/api/microsoft.extensions.dependencyinjection.optionsservicecollectionextensions.addoptions

Also, see the NuGet package (version history and dependencies):
https://www.nuget.org/packages/Microsoft.Extensions.DependencyInjection/

[schmik]

Sorry @IEvangelist, I am a little late.

If I visit the reference docs https://docs.microsoft.com/de-de/dotnet/api/microsoft.extensions.dependencyinjection.optionsservicecollectionextensions.addoptions?view=netstandard-2.0: there is this note "The requested page is not available for .NET Standard 2.0. You have been redirected to the newest product version this page is available for."

Accordingly, my VS refuses to convince the compiler to compile:

I created a minimal csproj: https://github.com/schmik/OptionsPatternsGuidanceParameterless/tree/master