C# & WPF Language support

I am working on an existing solution and there are hard-coded strings all over the place. We are wanting to offer a multi-language version of the app*, so need to localise in both C# code and WPF in 2 places:

> App.Core
>
> This project is C# and contains ViewModels etc.
>
> It is also responsible for raising notifications (Windows System
> notifications & custom UI notifications) and provides data to the WPF
> project, so these strings would need to be localised.

> App.Windows
>
> This project is a mix of WPF and C# classes.
>
> It has UI interfaces, buttons labels etc. The values for these come
> from within this project or are provided by the App.Core project.

I have looked at a few articles on how to localise (localize) but they seem to cover either localising C# or WPF, not really a combination of the two. I have tried some approaches out, but am not completely happy with them, maybe they work for C# but not for WPF and vice-versa.

Ideally, we want the user to be able to change their language while the app is running, so need to make sure this is possible (somehow)

*We are only expecting to use a handful of languages at this point (Dutch, English, French, German)

Any help, suggestions or advice would be very welcomed. TIA

The most common way to handle UI strings is in resx-files. This makes them available both in code, and they should also be accessible in xaml-files. If you have multiple projects you may need to configure the 'custom tool' in the properties to PublicResXFileCodeGenerator to make the generated files public.

If you want real time update when changing language you could use something like WPFLocalizeExtension when binding to strings in xaml code. If you are using UI strings in code you need to ensure all strings are updated when the language is changed. There is as far as I know no builtin or convenient way to do this.