https://learn.microsoft.com/ja-jp/dotnet/api/system.windows.markup.staticextension.providevalue?view=netframework-4.8.1&viewFallbackFrom=windowsdesktop-10.0
StaticExtension.ProvideValue(IServiceProvider) Method (System.Windows.Markup) | Microsoft Learn
Returns an object value to set on the property where you apply this extension. For StaticExtension, the return value is the static value that is evaluated for...
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