WPFLocalizeExtension

The extension is designed to work within visual designers like MS Visual Studio and MS Expression Blend without requiring a separate preview application.

• Design-Time Availability: Works for standard assemblies at design time. (Note: Dynamic loaded assemblies that are only found at runtime may not be available unless the .resx is built at design time).
• DesignValue Property: Use the DesignValue property to provide custom values to be displayed during design mode.
• Visual Testing: You can define a specific design language to facilitate visual testing of your UI layouts in the designer.

The {lex:Loc} extension implements a "Don't Repeat Yourself" (DRY) strategy. If you do not provide a Key, the extension automatically generates one based on the element's x:Name and the target property being set.

Example:

<Button x:Name="MyButton" Content="{lex:Loc}" ToolTip="{lex:Loc}" FontSize="{lex:Loc}"/>

In this case, the extension searches the default assembly and default resources for the following keys:

• MyButton_Content (string)
• MyButton_ToolTip (string)
• MyButton_FontSize (double)

If the resource type differs from the target property type, the extension attempts to convert it automatically. It uses TypeConverters and includes a built-in converter to map Bitmap resources to WPF BitmapSource types.

<Button x:Name="MyButton" Content="{lex:Loc}" />
<!-- Searches for key: MyButton_Content -->

You can control where the extension looks for localized strings by configuring providers. This allows you to switch localization sources at different levels of your application's visual tree.

• Global Configuration: Use the DefaultProvider property on LocalizeDictionary to set the provider for the entire application.
• Sub-tree Configuration: Use the Provider property on a LocalizeDictionary instance at an arbitrary node to change the provider for that specific sub-tree.
• Built-in Provider: The default provider is the RESX provider, which performs standard resource file lookups and is fully backward compatible.
• Custom Providers: You can implement your own provider by using the provided interface. An example implementation using CSV is available in the project's Tests folder.

The LocExtension automatically determines the target property's type and attempts to find an appropriate TypeConverter.

• Standard Types: Most types are supported via standard WPF TypeConverter logic.
• Bitmaps: The extension includes a built-in converter to transform Bitmap (from resource files) into BitmapSource (WPF).
• Enums: Enum types are supported natively and do not require specific converters.
• Custom Conversions: If you encounter an unsupported type, you can provide a custom IValueConverter by passing it as the Converter property and providing a ConverterParameter within the LocExtension declaration.

You can extend the library's localization capabilities by plugging in a custom localization provider. To do this, implement the ILocalizationProvider interface.

By default, the extension uses a provider that supports .resx files, which can be distributed across multiple assemblies in your project. You can replace this default provider with your own implementation (for example, a provider for CSV files) by configuring the localization providers settings.

If you omit the key in the {lex:Loc} extension, the extension attempts to automatically resolve a key based on the control's Name or x:Name property. It searches for matching resource keys using the following priority order:

1. ControlName_PropertyName (e.g., MyButton_Content for a Button's Content property).
2. ControlName (e.g., MyButton).

If neither pattern matches a key in your localization resources, no value will be provided.

<!-- If Name is 'MyButton', it looks for 'MyButton_Content' then 'MyButton' -->
<Button Name="MyButton" Content="{lex:Loc}" />

For complex strings that require dynamic values or pluralization (e.g., "You have selected 10 car(s)."), the extension provides a StringFormatConverter.

This converter integrates with smartFormat if it is available in the project, allowing for advanced template-based string manipulation and pluralization logic.

You can provide the localization key to the lex:Loc extension in two ways:

1. Directly after the extension name: Use the syntax {lex:Loc KeyName}.
2. Using the Key property: Use the syntax {lex:Loc Key=KeyName}.

Both methods are functionally identical.

<!-- Method 1: Direct -->
<Button Content="{lex:Loc Test}" />

<!-- Method 2: Key property -->
<Button Content="{lex:Loc Key=Test}" />

By default, culture-specific .resx files may appear as separate items in the Solution Explorer. To group them under the main resource file in a treeview structure, you must manually edit your .csproj file using the DependentUpon syntax.

1. Unload the project.
2. Edit the .csproj file.
3. Locate the <EmbeddedResource> tags and ensure the culture-specific files use <DependentUpon> pointing to the main resource file, while the main file uses the ResXFileCodeGenerator.

    <EmbeddedResource Include="Strings.de.resx">
      <SubType>Designer</SubType>
      <DependentUpon>Strings.resx</DependentUpon>
    </EmbeddedResource>
    <EmbeddedResource Include="Strings.resx">
      <Generator>ResXFileCodeGenerator</Generator>
      <LastGenOutput>Strings.Designer.cs</LastGenOutput>
    </EmbeddedResource>