iOS DateFormatter Returns Null - ios

I want to get day/month and hour:minute from "12/10/2015 6:11:04 PM" format date. I am from Turkey so our date format is 23 hours. When I use the code below, it returns date "nil".
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"UTC"]];
[dateFormatter setLocale:[[NSLocale alloc] initWithLocaleIdentifier:#"tr_TR_POSIX"]];
[dateFormatter setDateFormat:#"d/m/yyyy h:mm:ss a"];
NSDate *date = [dateFormatter dateFromString:#"12/10/2015 6:11:04 PM"];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:(NSCalendarUnitHour | NSCalendarUnitMinute) fromDate:date];
NSInteger hour = [components hour];
NSInteger minute = [components minute];

change dateformat like and try
[dateFormatter setDateFormat:#"dd/MM/yyyy h:mm:ss a"];

Related

Strange NSDate after changing hour

I want to change hour in NSDate. I did something like this:
NSDate *final = [gregorian dateBySettingUnit:NSCalendarUnitHour value:hour.intValue ofDate:self.dateForNewEvent options:NSCalendarMatchStrictly];
where self.dateForNewEvent = 2018-07-09 07:24:13 +0000
and hour.intValue = 5 and i expect date = 2018-07-09 05:00:00 + 0000 but i got 2018-07-10 03:00:00 UTC. How should I do it to get expected date ?
To change the hours of a specific NSDate, you need to manipulate it via NSDateComponents. Please try below code for the same:
NSDate *now = [NSDate date]; // YOUR DATE INSTANCE
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier: NSCalendarIdentifierGregorian];
NSDateComponents *components = [calendar components:NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay|NSCalendarUnitHour|NSCalendarUnitMinute|NSCalendarUnitSecond fromDate:now];
[components setHour:5];
NSDate *today5am = [calendar dateFromComponents:components];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
[dateFormatter setTimeStyle:NSDateFormatterMediumStyle];
NSLog(#"Date ===>>> %#",[dateFormatter stringFromDate:[NSDate date]]);
Hope this helps!
I think you are mixing NSDate with NSCalendar: NSDate is a point in time, internally represented in UTC. To get the local date/time as it is displayed on a calendar or watch , you use NSCalendar.
So if you are in MEST (UTC+2) and set the time to "5" hours on your calendar, this will be UTC "3" hours.
To get the calendar date/time back, you could use components(_:from:) from NSCalendar.
Just check this code:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"yyyy-MM-dd'T'HH:mm:ssZZZZZ"];
NSDate * dateForNewEvent = [dateFormatter dateFromString: #"2018-07-09T07:24:13+00:00"];
NSLog(#"dateForNewEvent: %#", dateForNewEvent);
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
NSDateComponents *comps = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear|NSCalendarUnitHour|NSCalendarUnitMinute fromDate:dateForNewEvent];
[comps setHour:5];
NSDate *final = [gregorian dateFromComponents:comps];
NSLog(#"final: %#", final);
Output as expected:
2018-07-09 11:11:43.542 jdoodle[22:22] dateForNewEvent: 2018-07-09 07:24:13 +0000
2018-07-09 11:11:43.542 jdoodle[22:22] final: 2018-07-09 05:24:00 +0000

iOS set date to MM//DD/YY 00:00:00

I know there's a few questions already on this but I keep running into the same error regardless of what I do to my code. I am working in the simulator, I have location set to my long/lat. When I try to convert the current date to zero hours, minutes, seconds I always get this result:
2015-07-10 08:53:19.868 xxxxxxxxxxxxxxxxx[2184:7462272] Today at start of day:2015-07-10 04:00:00 +0000
Here's my code:
NSDate* today = [[NSDate alloc] init];
NSCalendar* currentCalendar = [NSCalendar currentCalendar];
NSDateComponents* dateComponents = [currentCalendar components:NSCalendarUnitMonth | NSCalendarUnitDay | NSCalendarUnitYear fromDate:today];
NSInteger thisMonth = [dateComponents month];
NSInteger thisDay = [dateComponents day];
NSInteger thisYear = [dateComponents year];
NSDateComponents* dayComponents = [[NSDateComponents alloc] init];
[dayComponents setDay:thisDay];
[dayComponents setMonth:thisMonth];
[dayComponents setYear:thisYear];
NSDate* todayAtMidnight = [currentCalendar dateFromComponents:dayComponents];
NSLog(#"Today at start of day:%#", todayAtMidnight);
Even if add
[dayComponents setHour:0]; the hour still comes out as 4.
What am I doing wrong?
To get the beginning of today you can use
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit
fromDate:[NSDate date]];
[calendar setTimeZone:[NSTimeZone timeZoneWithName:#"GMT"]];
NSLog(#"date %#", [calendar dateFromComponents:components]);
Make sure you have the correct timezone
2015-07-10 04:00:00 +0000 is UTC, not your local timezone.
To display it in your local timezone, use an NSDateFormatter:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.dateFormat = #"yyyy-MM-dd HH:mm";
[dateFormatter setTimeZone:[NSTimeZone systemTimeZone]];
NSLog([dateFormatter stringFromDate:todayAtMidnight]);
Use NSDateFormatter as follow because system timezone is UTC:
NSDateFormatter * formatter = [[NSDateFormatter alloc] init];
[formatter setTimeZone:[NSTimeZone timeZoneWithName:#"GMT"]];
[formatter setDateFormat:#"yyyy-MM-dd HH:mm:ss"];
NSDate * curDate = [formatter dateFromString:[NSDate date]];
Then you'll get 2015-07-10 00:00:00.

get islamic data and georgian date in specific format in ios

i want to get the current date in format like this 24 February 2014 . i want
also get Islamic date in the same format as 5 jumada al-awwal 1436
how can i do that i saw other thing but most care about integer components.
i wrote this code which just get components
NSDateComponents *components = [[NSCalendar currentCalendar] components:NSCalendarUnitDay | NSCalendarUnitMonth | NSCalendarUnitYear fromDate:[NSDate date]];
NSInteger day = [components day];
NSInteger month = [components month];
NSInteger year = [components year];
NSLog(#"%#",components);
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"EEEE"];
NSLog(#"%#", [dateFormatter stringFromDate:[NSDate date]]);
i used this to Islamic date
NSCalendar *islamicCalendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSIslamicCalendar];
NSDate *today = [NSDate date];
[islamicCalendar rangeOfUnit:NSDayCalendarUnit startDate:&today interval:NULL forDate:today];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setCalendar:islamicCalendar];
[dateFormatter setTimeStyle:NSDateFormatterFullStyle];
[dateFormatter setDateStyle:NSDateFormatterFullStyle];
//english output
dateFormatter.locale = [[NSLocale alloc] initWithLocaleIdentifier:#"en_US_POSIX"];
NSString * islamicDateString = [dateFormatter stringFromDate:today];
NSLog(#"%#", islamicDateString);

setting time when formatting date using NSDateformatter

I have following code to convert string to date. Is it possible that it sets time as "00:00:00" and not the current time?
NSDateFormatter *dateformat = [[NSDateFormatter alloc] init];
[dateformat setDateFormat:#"yyyy-MM-dd"];
NSString *str = #"2014-08-08";
NSDate *dt = [dateformat dateFromString:str];
This gives dt as "2014-08-08 15:20:00 +0000" because I did the operation at 15:20.
Edit: I am using this date to convert it to integer later to store it in database:
int t = [dt timeIntervalSince1970];
If you are displaying the date dt with NSLog you will see what the date description method provides. If you want to see the date in a specific way that suits you use NSDateFormatter to format the date.
Example:
NSDateFormatter *dateformat = [[NSDateFormatter alloc] init];
[dateformat setDateFormat:#"yyyy-MM-dd"];
NSString *str = #"2014-08-08";
NSDate *dt = [dateformat dateFromString:str];
NSDateFormatter *displayDateformat = [[NSDateFormatter alloc] init];
[displayDateformat setDateFormat:#"yyyy-MM-dd"];
NSString *displayDateString = [displayDateformat stringFromDate:dt];
NSLog(#"displayDateString: %#", displayDateString);
Output:
2014-08-08
Note per Apple docs: "This method returns a time value relative to an absolute reference dateā€”the first instant of 1 January 2001, GMT."
A good practice is to use NSDateComponents
NSDate *yourDate = [NSDate date];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *dateComponents = [calendar components:(NSYearCalendarUnit | NSMonthCalendarUnit | NSDayCalendarUnit) fromDate:yourDate];
[calendar setTimeZone:[NSTimeZone localTimeZone]];
// Set the time components manually
[dateComponents setHour:0];
[dateComponents setMinute:0];
[dateComponents setSecond:0];
yourDate = [calendar dateFromComponents:dateComponents];
Update
iOS8 :
[[NSCalendar currentCalendar] startOfDayForDate:[NSDate date]];

Comparing 2 dates, error in NSDateComponents

I have 2 dates. Date1 in yyyy-MM-dd 21:00:00 +0000. Date2 in yyyy-MM-dd
I need to compare it and get age result.
Problem is that Ia have an error in NSDateComponents string.
NSDate *date1 = [NSDate date];
NSDate *date2temp = uBirthdate;
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"yyyy-MM-dd"];
NSString *dateString = [dateFormatter stringFromDate:date2temp];
[dateString stringByAppendingString:#" 21:00:00 +0000"];
NSDate *date2 = [dateFormatter dateFromString:dateString];
NSCalendar *calendar = [NSCalendar currentCalendar];
NSDateComponents *components = [calendar components:NSYearCalendarUnit fromDate:date2 toDate:date1 options:0];
NSInteger editedAge = components.year;
NSLog(#"%d ", editedAge);
It will be better to cut off '21:00:00 +0000' from date1, but I do not know how can I do it

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