[objective-c] Convert NSDate to NSString

How do I convert, NSDate to NSString so that only the year in @"yyyy" format is output to the string?

If you don't have NSDate -descriptionWithCalendarFormat:timeZone:locale: available (I don't believe iPhone/Cocoa Touch includes this) you may need to use strftime and monkey around with some C-style strings. You can get the UNIX timestamp from an NSDate using NSDate -timeIntervalSince1970.

NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:(NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay) fromDate:myNSDateInstance];
NSInteger year = [components year];
// NSInteger month = [components month];
NSString *yearStr = [NSString stringWithFormat:@"%ld", year];

In Swift:

var formatter = NSDateFormatter()
formatter.dateFormat = "yyyy"
var dateString = formatter.stringFromDate(YourNSDateInstanceHERE)

If you are on Mac OS X you can write:

NSString* s = [[NSDate date] descriptionWithCalendarFormat:@"%Y_%m_%d_%H_%M_%S" timeZone:nil locale:nil];

However this is not available on iOS.

Hope to add more value by providing the normal formatter including the year, month and day with the time. You can use this formatter for more than just a year

[dateFormat setDateFormat: @"yyyy-MM-dd HH:mm:ss zzz"]; 

there are a number of NSDate helpers on the web, I tend to use:

https://github.com/billymeltdown/nsdate-helper/

Readme extract below:

  NSString *displayString = [NSDate stringForDisplayFromDate:date];

This produces the following kinds of output:

‘3:42 AM’ – if the date is after midnight today
‘Tuesday’ – if the date is within the last seven days
‘Mar 1’ – if the date is within the current calendar year
‘Mar 1, 2008’ – else ;-)

Just add this extension:

extension NSDate {
    var stringValue: String {
        let formatter = NSDateFormatter()
        formatter.dateFormat = "yourDateFormat"
        return formatter.stringFromDate(self)
    }
}

#ios #swift #convertDateinString

Simply just do like this to "convert date into string" as per format you passed:

let formatter = DateFormatter()

formatter.dateFormat = "dd-MM-YYYY" // pass formate here
        
let myString = formatter.string(from: date) // this will convert Date in String

Note: You can specify different formats such like "yyyy-MM-dd", "yyyy", "MM" etc...

I don't know how we all missed this: localizedStringFromDate:dateStyle:timeStyle:

NSString *dateString = [NSDateFormatter localizedStringFromDate:[NSDate date] 
                                                      dateStyle:NSDateFormatterShortStyle 
                                                      timeStyle:NSDateFormatterFullStyle];
NSLog(@"%@",dateString);

outputs '13/06/12 00:22:39 GMT+03:00'

It's swift format :

func dateFormatterWithCalendar(calndarIdentifier: Calendar.Identifier, dateFormat: String) -> DateFormatter {

    let formatter = DateFormatter()
    formatter.calendar = Calendar(identifier: calndarIdentifier)
    formatter.dateFormat = dateFormat

    return formatter
}


//Usage
let date = Date()
let fotmatter = dateFormatterWithCalendar(calndarIdentifier: .gregorian, dateFormat: "yyyy")
let dateString = fotmatter.string(from: date)
print(dateString) //2018

Define your own utility for format your date required date format for eg.

NSString * stringFromDate(NSDate *date)  
 {   NSDateFormatter *formatter
    [[NSDateFormatter alloc] init];  
    [formatter setDateFormat:@"MM / dd / yyyy, hh?mm a"];    
    return [formatter stringFromDate:date]; 
}

  NSDateFormatter *dateformate=[[NSDateFormatter alloc]init];
  [dateformate setDateFormat:@"yyyy"]; // Date formater
  NSString *date = [dateformate stringFromDate:[NSDate date]]; // Convert date to string
  NSLog(@"date :%@",date);

+(NSString*)date2str:(NSDate*)myNSDateInstance onlyDate:(BOOL)onlyDate{
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    if (onlyDate) {
        [formatter setDateFormat:@"yyyy-MM-dd"];
    }else{
        [formatter setDateFormat: @"yyyy-MM-dd HH:mm:ss"];
    }

    //Optionally for time zone conversions
    //   [formatter setTimeZone:[NSTimeZone timeZoneWithName:@"..."]];

    NSString *stringFromDate = [formatter stringFromDate:myNSDateInstance];
    return stringFromDate;
}

+(NSDate*)str2date:(NSString*)dateStr{
    if ([dateStr isKindOfClass:[NSDate class]]) {
        return (NSDate*)dateStr;
    }

    NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
    [dateFormat setDateFormat:@"yyyy-MM-dd"];
    NSDate *date = [dateFormat dateFromString:dateStr];
    return date;
}

swift 4 answer

static let dateformat: String = "yyyy-MM-dd'T'HH:mm:ss"
public static func stringTodate(strDate : String) -> Date
{

    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = dateformat
    let date = dateFormatter.date(from: strDate)
    return date!
}
public static func dateToString(inputdate : Date) -> String
{

    let dateFormatter = DateFormatter()
    dateFormatter.dateFormat = dateformat
    return formatter.string(from: inputdate)

}