Convert NSString to NSDate and back again using NSDateFormatter

March 09, 2021

How to convert NSString to NSDate and back again using NSDateFormatter in any format - Objective C ?

Convert NSString to NSDate

    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    formatter.dateFormat = @"MMMM dd, yyyy";
    formatter.locale = [NSLocale localeWithLocaleIdentifier: @"en_US_POSIX"];
    NSString *dateString = @"April 15, 2021";
    NSDate *date = [formatter dateFromString:dateString];

While using fixed format dates we need to set the date formatter locale to “en_US_POSIX”

en_US_POSIX is a locale designed to yield US English results regardless of both user and system preferences.

en_US_POSIX will be invariant with time and platforms.

If en_US might change in future it will not impact how en_US_POSIX format dates. So it's safe to use en_US_POSIX while working on fixed format dates.

convert NSDate to NSString

     formatter.locale = [NSLocale currentLocale];
     NSString *newString =  [formatter stringFromDate:date];