Ordinal Month-day Suffix Option for NSDateFormatter setDateFormat

This is easily done as of iOS9

NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];
formatter.numberStyle = NSNumberFormatterOrdinalStyle;
NSArray<NSNumber *> *numbers = @[@1, @2, @3, @4, @5];

for (NSNumber *number in numbers) {
    NSLog(@"%@", [formatter stringFromNumber:number]);
}
// "1st", "2nd", "3rd", "4th", "5th"

Taken from NSHipster

Swift 2.2:

let numberFormatter = NSNumberFormatter()
numberFormatter.numberStyle = .OrdinalStyle
let numbers: [Int] = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
for number in numbers {
    print(numberFormatter.stringFromNumber(number)!)
}

Here's another implementation for a method to generate the suffix. The suffixes it produces are only valid in English and may not be correct in other languages:

- (NSString *)suffixForDayInDate:(NSDate *)date
{
    NSInteger day = [[[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar] components:NSDayCalendarUnit fromDate:date] day];
    if (day >= 11 && day <= 13) {
        return @"th";
    } else if (day % 10 == 1) {
        return @"st";
    } else if (day % 10 == 2) {
        return @"nd";
    } else if (day % 10 == 3) {
        return @"rd";
    } else {
        return @"th";
    }
}

None of these answers were as aesthetically pleasing as what I'm using, so I thought I would share:

---

Swift 3:

func daySuffix(from date: Date) -> String {
    let calendar = Calendar.current
    let dayOfMonth = calendar.component(.day, from: date)
    switch dayOfMonth {
    case 1, 21, 31: return "st"
    case 2, 22: return "nd"
    case 3, 23: return "rd"
    default: return "th"
    }
}

---

Objective-C:

- (NSString *)daySuffixForDate:(NSDate *)date {
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSInteger dayOfMonth = [calendar component:NSCalendarUnitDay fromDate:date];
    switch (dayOfMonth) {
        case 1:
        case 21:
        case 31: return @"st";
        case 2:
        case 22: return @"nd";
        case 3:
        case 23: return @"rd";
        default: return @"th";
    }
}

---

Obviously, this only works for English.

NSDate *date = [NSDate date];
NSDateFormatter *prefixDateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[prefixDateFormatter setFormatterBehavior:NSDateFormatterBehavior10_4];
[prefixDateFormatter setDateFormat:@"h:mm a EEEE MMMM d"];
NSString *prefixDateString = [prefixDateFormatter stringFromDate:date];
NSDateFormatter *monthDayFormatter = [[[NSDateFormatter alloc] init] autorelease];
[monthDayFormatter setFormatterBehavior:NSDateFormatterBehavior10_4];
[monthDayFormatter setDateFormat:@"d"];     
int date_day = [[monthDayFormatter stringFromDate:date] intValue];  
NSString *suffix_string = @"|st|nd|rd|th|th|th|th|th|th|th|th|th|th|th|th|th|th|th|th|th|st|nd|rd|th|th|th|th|th|th|th|st";
NSArray *suffixes = [suffix_string componentsSeparatedByString: @"|"];
NSString *suffix = [suffixes objectAtIndex:date_day];   
NSString *dateString = [prefixDateString stringByAppendingString:suffix];   
NSLog(@"%@", dateString);