CultureInfo.TextInfo.IsRightToLeft returns false for Uyghur culture in Blazor WebAssembly

[abduwaris]

Is there an existing issue for this?

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Describe the bug

I have encountered an issue with the CultureInfo.TextInfo.IsRightToLeft property in Blazor WebAssembly. Specifically, when using the Uyghur culture (ug-CN), the IsRightToLeft property returns false, which is not the expected behavior since Uyghur is a right-to-left language.

In Blazor WebAssembly, the following code snippet returns false:

@page "/text-direction"

@using System.Globalization

<div>
    @if (ugCulture.TextInfo.IsRightToLeft)
    {
        <p>The text direction is set to Right-To-Left.</p>
    }
    else
    {
        <p>The text direction is set to Left-To-Right.</p>
    }
</div>

@code {
    private CultureInfo ugCulture;

    protected override void OnInitialized()
    {
        ugCulture = new CultureInfo("ug-CN");
    }
}

This behavior may affect the rendering of Uyghur text in Blazor applications, as proper text direction is crucial for correct display and user experience.

If there is a known workaround or if this behavior is expected, please let me know. Otherwise, I would appreciate any guidance on how this issue might be addressed in future updates.

Thank you!

Expected Behavior

For the Uyghur culture (ug-CN), I expect the TextInfo.IsRightToLeft property to return true.

Steps To Reproduce

No response

Exceptions (if any)

No response

.NET Version

9.0.100

Anything else?

No response

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[tarekgh]

@ilonatommy

[ilonatommy]

ug-CN is not a supported culture in WASM apps by default. It is same issue as e.g. #104717. You can prepare ICU data for your app by adding ug_CN to filters and build it from source, then replace the default icu data, following the instructions from https://github.com/dotnet/runtime/blob/ca0011a9698ec113535b710285bdda942ec5bd2b/docs/design/features/globalization-icu-wasm.md#custom-icu

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