Slang.NET

Type-safe i18n for .NET

About this library

Slang.NET is a .NET port of the slang from the Dart/Flutter community with new features (like string format).

You can view how the generated files general, en, and de look

Getting Started:

Install the library as a NuGet package:

Install-Package dotnet add package Slang.Net

Add JSON files:

Important file must end with ".i18n.json". This is necessary so that the SourceGenerator does not track changes to other AdditionalFiles.

i18n/strings_en.i18n.json or i18n/strings_en-US.i18n.json or i18n/strings.i18n.json (for base culture)

{
  "screen": {
    "locale1": "Locale 1"
  }
}

i18n/strings_ru.i18n.json or i18n/strings_ru-RU.i18n.json

{
  "screen": {
    "locale1": "Локаль 1"
  }
}

slang.json

{
  "base_culture": "en" // or "en-EN"
}

Recommendation It is recommended to specify the country code, such as "en-US," for proper functionality when formatting strings, especially if you will be retrieving the list of cultures from SupportedCultures.

Include JSON files as AdditionalFiles:

  <ItemGroup>
    <AdditionalFiles Include="i18n\*.i18n.json" />
    <AdditionalFiles Include="slang.json" />
  </ItemGroup>

Add a partial class:

[Translations(InputFileName = "strings")]
public partial class Strings;

Done!

Strings.SetCulture(new CultureInfo("ru-RU")); 

Console.WriteLine(Strings.Instance.Root.Screen.Locale1); // Локаль 1

Strings.SetCulture(new CultureInfo("en-US"));

Console.WriteLine(Strings.Instance.Root.Screen.Locale1); // Locale 1

or

  <MenuItem  Header="{Binding Root.Screen.Locale1, Source={x:Static localization:Strings.Instance}}" />

Features

• String Interpolation
• Typed Parameters
• Comments
• String Format
• Pluralization
• Linked Translations
• Maps
• Lists

String Interpolation

You can specify parameters passed at runtime..

"Hello": "Hello {name}"

The generated code will look like this:

/// In en, this message translates to:
/// **"Hello {name}"**
public virtual string Hello(object name) => $"Hello {name}";

Typed Parameters

Parameters are typed as object by default. This is convenient because it offers maximum flexibility.

You can specify the type using two syntax options: 1 - Simple:

{
  "greet": "Hello {name: string}, you are {age: int} years old"
}

2 - Using a placeholders, which allows you to specify a type or format string (see String Format).

{
  "greet2": "Hello {name}, you are {age} years old",
  "@greet2": {
    "placeholders": {
      "name": {
        "type": "string"
      },
      "age": {
        "type": "int"
      }
    }
  },
}

The generated code will look like this:

/// In ru, this message translates to:
/// **"Hello {name}, you are {age} years old"**
public virtual string Greet(string name, int age) => $"Hello {name}, you are {age} years old";

Comments

You can add comments to your translation files.

{
  "@@locale": "en", // fully ignored
  "mainScreen": {
    "button": "Submit",

    // ignored as translation but rendered as a comment
    "@button": "The submit button shown at the bottom",

    // or use 
    "button2": "Submit",
    "@button2": {
      "description": "The submit button shown at the bottom"
    }
  }
}

The generated code will look like this:

/// The submit button shown at the bottom
///
/// In ru, this message translates to:
/// **"Submit"**
public virtual string Button => "Submit";

String Format

Pluralization

Linked Translations

Maps

Lists

Tools

Translate with GPT

Take advantage of GPT to internationalize your app with context-aware translations.

Download slang-gpt.

Then add the following configuration in your slang.json:

{
  "base_culture": "ru",
  "gpt": {
    "model": "gpt-4o-mini",
    "description": "Showcase for Slang.Net.Gpt"
  }
}

Then use slang-gpt:

<cli-directory>/slang-gpt <csproj-path> --target=ru --api-key=<api-key>

See more: Documentation