Why a binding's StringFormat didn't use a current culture?

Question

My current culture is ru-RU. I need it to format decimal to currency string.

decimal n = 111.22M;

n.ToString("C") will return "111,22р."

but when I try to use StringFormat field of a binding I get a "$111.22" result

<TextBlock Text={Binding Number, StringFormat=C} />

Answer 1

By default, WPF will use English as the culture for binding StringFormat processing, not the thread's current culture.

You can override this by adding the following in the application's startup code:

FrameworkElement.LanguageProperty.OverrideMetadata(typeof(FrameworkElement),
    new FrameworkPropertyMetadata(      XmlLanguage.GetLanguage(CultureInfo.CurrentCulture.IetfLanguageTag)));

For details, see Josh Smith's article on Creating an Internationalized Wizard.