Spanish (United States) Locale
Last week, I had a enquiry from a customer about the Spanish locale for the United States. As he mentioned, it does make sense to have this locale, especially for the users based in the southern regions of the US. If you are running Windows XP or Windows Server 2003, there is no such locale supported by the operating system so if you try to access this locale in a managed application by writing this line of code:
System.Globalization.CultureInfo cultureInfo = new System.Globalization.CultureInfo("es-US");
you will get an ArgumentException, which says: "Culture name 'es-US' is not supported". As a workaround, you can use the "es-MX" locale or create your own locale.
But the good news is that the support for the "es-US" locale was added in Windows Vista and Windows Server 2008 so if you are running one of these operating systems, you can now use the es-US locale (LCID = 21514) and the same line of code we used above will work fine.
This page has a complete list of the locale IDs assigned by Microsoft so if you thinking of creating your own locale, check this list first to make sure there is no conflict with the existing locales.