Make PortableObjectStringLocalizer simpler for inheritance

[hishamco]

Fixes #9542

[Skrypt]

I'm not sure if this is necessary. Why would you want to inherit the PortableObjectStringLocalizer?

[hishamco]

There are some case to allow developers to subclass the localizer. I remember one example is to allow multiple path to load the localization resources from. Make the members open some extensibility

@amolodenov you can mention your use case if it's possible

[amolodenov]

There are some case to allow developers to subclass the localizer. I remember one example is to allow multiple path to load the localization resources from. Make the members open some extensibility

@amolodenov you can mention your use case if it's possible

I need to use few cultures at the same time. For this, I planned to implement an analogue https://github.com/aspnet/Localization/blob/master/src/Microsoft.Extensions.Localization/ResourceManagerWithCultureStringLocalizer.cs, but PortableObjectStringLocalizer did not allow inherit correctly. I know ResourceManagerWithCultureStringLocalizer is obsolete, but changing CurrentCulture doesn't suit for me.
My example

public class PortableObjectWithCultureStringLocalizer : PortableObjectStringLocalizer
{
    private readonly ILocalizationManager _localizationManager;
    private readonly bool _fallBackToParentCulture;
    private readonly ILogger _logger;
    private readonly string _context;
    private readonly CultureInfo _culture;

    public PortableObjectWithCultureStringLocalizer(
        string context,
        ILocalizationManager localizationManager,
        bool fallBackToParentCulture,
        CultureInfo culture,
        ILogger logger)
        : base(context, localizationManager, fallBackToParentCulture, logger)
    {
        _context = context;
        _localizationManager = localizationManager;
        _fallBackToParentCulture = fallBackToParentCulture;
        _culture = culture;
        _logger = logger;
    }

    public override LocalizedString this[string name]
    {
        get
        {
            if (name == null)
            {
                throw new ArgumentNullException(nameof(name));
            }

            var translation = GetTranslation(name, _context, _culture, null);

            return new LocalizedString(name, translation ?? name, translation == null);
        }
    }

    public override LocalizedString this[string name, params object[] arguments]
    {
        get
        {
            var (translation, argumentsWithCount) = GetTranslation(name, arguments);
            var formatted = string.Format(translation.Value, argumentsWithCount);

            return new LocalizedString(name, formatted, translation.ResourceNotFound);
        }
    }
   
   ...
}

[hishamco]

Any update on this, I think the idea to make the localizer more extensible nothing else

[Skrypt]

/cc @sebastienros

[hishamco]

Can we triage this?

[sebastienros]

Merging, but we should not make it a habit. It's exposing things we might regret as it's increasing the burden on breaking changes for future versions. One can easily copy the code if necessary. There isn't much value in inheriting directly from it.

[hishamco]

Sometimes there's a need to customize the default behavior, Copy paste is not good all the time ;)