Question

Does anyone know exactly what the new (iOS 6) lowercaseStringWithLocale method of NSString does? The documentation is very skimpy, and I didn’t find a single reference to this method in Apple’s developer forums.

While localizing my app, I’m interested in changing words from my strings file to lowercase when they appear in a sentence — except in the German version, where some words should stay in uppercase at all times. Is that what this method is for? Or something completely different?

Answer 1

The discussion in lowercaseString might shed some light:

Note: This method performs the canonical (non-localized) mapping. It is suitable for programming operations that require stable results not depending on the user’s locale preference. For localized case mapping for strings presented to users, use the corresponding lowercaseStringWithLocale: method.

So if you’re computing the lowercase version of a string for a purpose such as case-insensitive database lookup, use lowercaseString. If you intend to show the user the result, then use lowercaseStringWithLocale.

Note that lowercaseStringWithLocale won’t make a decision based on the actual words as to whether the word should be lowercased or not. It does what you ask it to do, and doesn’t question your motives.