Get current date and time in a well-kwnown format

How to get the current date and time printed out in standard formats?
Using NSDateFormatter is quite a joke, so this is a powerful function.


/** Get the current date and time in any of the standard formats.

 Parameter "format" must be one of these values:
 0: "dd/MM/yyyy - HH:mm"
 1: "dd_MM_yyyy_HH_mm_ss"
 2: "yyyy-MM-dd"
 3: "HH:mm:ss"
 4: "dd/MM/yyyy - HH:mm:ss"

 @param format Type of format and therefore also the result type.
 @return Returns a string representing the current date and time using selected format.

 */
+ (NSString *)currentDateAndTimeUsingFormatMode:(NSInteger)format {
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    switch (format) {
        case 0:
            [formatter setDateFormat:@"dd/MM/yyyy - HH:mm"];
            break;
        case 1:
            [formatter setDateFormat:@"dd_MM_yyyy_HH_mm_ss"];
            break;
        case 2:
            [formatter setDateFormat:@"yyyy-MM-dd"];
            break;
        case 3:
            [formatter setDateFormat:@"HH:mm:ss"];
            break;
        case 4:
            [formatter setDateFormat:@"dd/MM/yyyy - HH:mm:ss"];
            break;
        default:
            [formatter setDateFormat:@"dd/MM/yyyy - HH:mm"];
            break;
    }

    return [formatter stringFromDate:[NSDate date]];
}


Download the ready-for-use source file (.m) of Get current date and time in a well-kwnown format

Check if a string is a valid time format

Ever wonder to check if a NSString might represent a valid time? I mean, hours : minutes : seconds ...


/** Check whether a string is a valid time in standard format "HH:mm:ss".

 @param time String time to evaluate.
 @return Returns true if it's a valid string time, false otherwise.

 */
+ (BOOL)isValidTimeString:(NSString *)time {

    NSArray *temp = [time componentsSeparatedByString:@":"];
    if ([temp count] != 3) { return NO;    }

    NSString *h = [temp objectAtIndex:0];
    NSString *m = [temp objectAtIndex:1];
    NSString *s = [temp objectAtIndex:2];

    // Minutes and seconds must be of two digits. Hours, instead, might have any digits.
    if (m.length != 2) { return NO;    }
    if (s.length != 2) { return NO;    }

    // Check values are numeric.
    NSCharacterSet *num09 = [NSCharacterSet decimalDigitCharacterSet];
    if (![num09 isSupersetOfSet:[NSCharacterSet characterSetWithCharactersInString:h]]) { return NO; }
    if (![num09 isSupersetOfSet:[NSCharacterSet characterSetWithCharactersInString:m]]) { return NO; }
    if (![num09 isSupersetOfSet:[NSCharacterSet characterSetWithCharactersInString:s]]) { return NO; }

    // Minute and second values must be lesser than 60.
    if ([m integerValue] >= 60) { return NO; }
    if ([s integerValue] >= 60) { return NO; }

    return YES;
}


Download the ready-for-use source file (.m) of Check if a string is a valid time format

Get current year

How to get current year in Objective-C using the Cocoa framework?
It works with both iOS (iPhone, iPad, iPod) and Mac OS systems.


/** Get current year.

 @return Returns the current year as integer.

 */
+ (NSInteger)getCurrentYear {
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *components = [gregorian components:NSYearCalendarUnit fromDate:[NSDate date]];
    return [components year];
}


Download the ready-for-use source file (.m) of Get current year