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Convert NSDate to NSString

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


S
Sunil Targe

How about...

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:@"yyyy"];

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

NSString *stringFromDate = [formatter stringFromDate:myNSDateInstance];

//unless ARC is active
[formatter release];

Swift 4.2 :

func stringFromDate(_ date: Date) -> String {
    let formatter = DateFormatter()
    formatter.dateFormat = "dd MMM yyyy HH:mm" //yyyy
    return formatter.string(from: date)
}

This will produce a memory leak, since the formatter is never released.
Don't use init with NSDateFormatter. It was removed after iOS 3.2. (And if you use a class method instead, it will autorelease and you won't have the leak problem, too.)
Really suggest looking below at localizedStringFromDate
@zekel I'm not sure what the documentation used to say, but now it suggests init in multiple places.
I would have autoreleased it (3 years ago)
O
Oded Ben Dov

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'


once written out to a string, is there a nice neat way to read it in like this? (using those NSDateFormatter enums)
@Fonix I don't think so - this is a localized string, which means it depends on the user's locale settings. You should never store dates in a format like this because the settings can change any time.
Its nice if you use the formatter rare. Otherwise you need a cache.
In swift: let dateString = NSDateFormatter.localizedStringFromDate(date, dateStyle: .ShortStyle, timeStyle: .FullStyle);
Reduced the number of codes and thanks its working perfect
R
Ronan Boiteau

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"]; 

V
Venk

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 ;-)

This is definitely a great solution. Don't have to waste time worrying about how you want your dates to look, and can get on with coding. :)
D
Dave Patrick

In Swift:

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

In Swift 3.0 let formatter = DateFormatter() formatter.dateFormat = "yyyy" return formatter.string(from: date)
S
Steve Moser
  NSDateFormatter *dateformate=[[NSDateFormatter alloc]init];
  [dateformate setDateFormat:@"yyyy"]; // Date formater
  NSString *date = [dateformate stringFromDate:[NSDate date]]; // Convert date to string
  NSLog(@"date :%@",date);

"YYYY" gives the year for the current week not day. Use "yyyy" instead. See this SO question for more info. stackoverflow.com/questions/15133549/…
Thanks Steve moser :)
V
Venk

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.


G
Gank
+(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;
}

N
Nazariy Vlizlo

Just add this extension:

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

n
neoneye

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.


a
amin

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

K
Khurram awan

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)

}

M
Mehdi Ijadnazar

Use extension to have clear code

You can write an extension to convert any Date object to any desired calendar and any format

extension Date{
    func asString(format: String = "yy/MM/dd HH:mm",
                  for identifier: Calendar.Identifier = .persian) -> String {
        let formatter = DateFormatter()
        formatter.calendar = Calendar(identifier: identifier)
        formatter.dateFormat = format
        
        return formatter.string(from: self)
    }
}

Then use it like this:

let now = Date()

print(now.asString())  // prints -> 00/04/18 20:25
print(now.asString(format: "yyyy/MM/dd"))  // prints -> 1400/04/18
print(now.asString(format: "MM/dd", for: .gregorian))  //  prints -> 07/09  

To learn how to specify your desired format string take a look at this link.
For a complete reference on how to format dates see Apple's official Date Formatting Guide here.


S
Shamsiddin Saidov
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];

A
Ash

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]; 
}

f
fcdt

#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...


P
Pranav Kasetti

Update for iOS 15

iOS 15 now supports calling .formatted on Date objects directly without an explicit DateFormatter.

Example for common formats

Documentation

date.formatted() // 6/8/2021, 7:30 PM
date.formatted(date: .omitted, time: .complete) // 19:30
date.formatted(date: .omitted, time: .standard) // 07:30 PM
date.formatted(date: .omitted, time: .shortened) // 7:30 PM
date.formatted(date: .omitted, time: .omitted)

Alternative syntax

Documentation

// We can also specify each DateComponent separately by chaining modifiers.
date.formatted(.dateTime.weekday(.wide).day().month().hour().minute())
// Tuesday, Jun 8, 7:30 pm

// Answer to specific question
date.formatted(.dateTime.year())

J
Jules

for Objective-C:

NSDate *date = [NSDate dateWithTimeIntervalSinceNow:0];
NSDateFormatter *formatter = [NSDateFormatter new];
formatter.dateFormat = @"yyyy";
NSString *dateString = [formatter stringFromDate:date];

for Swift:

let now = Date()
let formatter = DateFormatter()
formatter.dateFormat = "yyyy"
let dateString = formatter.string(from: now) 

That's a good website for nsdateformatter.You can preview date strings with different DateFormatter in different local.

https://i.stack.imgur.com/gViTP.png


A
Andrew____Pls_Support_Ukraine

Simple way to use C# styled way to convert Date to String.

usage:

let a = time.asString()
// 1990-03-25


let b = time.asString("MM ∕ dd ∕ yyyy, hh꞉mm a")
// 03 / 25 / 1990, 10:33 PM

extensions:

extension Date {
    func asString(_ template: String? = nil) -> String {
        if let template = template {
            let df = DateFormatter.with(template: template)
            
            return df.string(from: self)
        }
        else {
            return globalDateFormatter.string(from: self)
        }
    }
}

// Here you can set default template for DateFormatter
public let globalDateFormatter: DateFormatter = DateFormatter.with(template: "y-M-d")

public extension DateFormatter {
    static func with(template: String ) -> DateFormatter {
        let df = DateFormatter()
        df.dateFormat = template
        return df
    }
}