c# - Detect current keyboard language/layout name in multi-language computer

Question

I am trying to develop an application in C# which required to detect user selected language (keyboard layout). However two languages are installed on my computer, the code always returns the default one, even I change the language before run the application.

InputLanguage myCurrentLanguage = InputLanguage.InstalledInputLanguages[1]; // here I can see collection of languages 
InputLanguage myCurrentLanguage2 = InputLanguage.CurrentInputLanguage; // always return first or default one

Is there any technique to detect the real selected / running language?

Answer 1

Thread.CurrentThread.CurrentCulture.TwoLetterISOLanguageName in the namespace System.Threading returns what you call the default culture and is not related to the keyboard layout. I.e. on my computer this returns "de", the culture I am using for date and number formatting. However, I am using an US-ASCII keyboard and .Culture.Name and .LayoutName from System.Windows.Forms.InputLanguage.CurrentInputLanguage return "en-US" and "US" respectively.

Thread.CurrentThread.CurrentCulture gives a lot of additional information like KeyboardLayoutId, DisplayName (localized culture name), EnglishName, DateTimeFormat and more.

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I made some tests and noticed a strange behavior. I displayed the Windows language bar and selected a secondary input language. But whenever I started a little test-WinForms application, the input language automatically switched back to the default language. Once the application was started, I switched back the input language to the secondary one. Now it stayed to this one.

In both cases this gave me the correct input language (the one displayed on the language bar):

lblInputLanguage.Text = InputLanguage.CurrentInputLanguage.Culture.Name;
lblKeyboardLayout.Text = InputLanguage.CurrentInputLanguage.LayoutName;

This thread on superuser might shed some light on the problem: How to avoid keyboard layout automatically changing on windows