dateFromString working in ios 6 but not in ios 5

Question

This code working on iOS 6.0 simulator, but not working on iOS 5.0

NSString *unformattedDate = @"2008-09-25T20:41:11.000+00:00";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.SSSZZZZZ"];
NSDate *dateFromString = [dateFormatter dateFromString:unformattedDate];
[dateFormatter setDateFormat:@"dd.MM.yy"];
NSLog(@"%@", [dateFormatter stringFromDate:dateFromString]);

What can be wrong?

Answer 1

Since the ZZZZZ date format specifier was added in iOS 6, you can't format dates that have a timezone in the +99:99 format with iOS 5. Both versions do support the +9999 format using ZZZZ. If you know that your date/time strings will always have a timezone with the colon, then you can strip the colon.

NSString *unformattedDate = @"2008-09-25T20:41:11.000+00:00";
NSRange range = [unformattedDate rangeOfString:@":" options:NSBackwardsSearch];
if (range.location != NSNotFound && range.location >= unformattedDate.length - 4) {
    unformattedDate = [unformattedDate stringByReplacingCharactersInRange:range withString:@""];
}
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
NSLocale *posix = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US_POSIX"];
[dateFormatter setLocale:locale];
[dateFormatter setDateFormat:@"yyyy-MM-dd'T'HH:mm:ss.SSSZZZZ"];
NSDate *dateFromString = [dateFormatter dateFromString:unformattedDate];
[dateFormatter setDateFormat:@"dd.MM.yy"];
NSLog(@"%@", [dateFormatter stringFromDate:dateFromString]);

Note that with fixed formats like this, you must set the formatter's locale to the special "en_US_POSIX" locale.