The drawback of localized days and month names

Here's a screenshot of the 2 ends of my taskbar :



The left end shows that my Windows UI is in English. The right end shows that even though I'm using Windows in English, I prefer to read dates in French. Cool ! And if I had a screenshot of my date and time control panel applet (the one you get when you double-click the clock), you'd see that while most texts are in English, the names of months is in French.

GetLocaleInfo() and GetDate/TimeFormat() allow your programs to display dates in user's language, exactly as Windows does. It even allows you to correctly display the first day of the week (Whether Sunday, Monday or anything else according to you user's locale). See LOCALE_SDAYNAME1, LOCALE_SMONTHNAME1, LOCALE_IFIRSTDAYOFWEEK et al.

However, my experience is that each time I sent an app featuring some day/months names, my colleagues at tech support and localization would send it back to me saying "Hey, Serge ! You put French days in the English calendar dialog ! Please fix it ASAP !"

No, I didn't ! You get the names in your language for free.
"Wheeew ! Coooool !" They say. But they would ask again the next time ;-)

Now, this little story points out a real problem : Language inconsistence. These auto-translations bring in a mix of languages in your UI, which is not good. Of course, it's up to you to decide if the advantage outweights the drawback. Your decision might not always be the same, according to the context.

BTW, appTranslator doesn't display dates but it displays a list of languages, which Windows can display in English, in the language of the Windows UI or the native name of the language.
It's not completely trivial to make a choice, especially after you read this.