I have two dates (written in two different NSString), for example
31/12/2011
and
31/03/2012
I have to check if today is in this range.
For read the date from the NSString, I'm doing this:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd/MM/yyyy"];
[dateFormatter setTimeZone:[NSTimeZone systemTimeZone]];
NSDate *mydate = [dateFormatter dateFromString:my_string];
NSLog(#"%#", mydate);
but, in this example, the log is this one
2011-12-30 23:00:00 +0000
2012-03-30 23:00:00 +0000
So it's one hour behind.
I know that using
NSString *string = [dateFormatter stringFromDate:my_date];
my string it will be ok, but I can't see if today is in the range using NSString (or not?)!
So I have to use NSDate, but how can I solve the "time zone" problem?
Also, I have this problem also using
[NSDate date];
It returns me one hour ago (and I don't want it, because if someone check at midnight, for the phone it will be the day before!)
The following should help:
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"EST"]];
for more details, please check out This question ... It looks similar. The "EST" can be replaced with whichever time zone is required.
I may be mistaken, but it looks, like you don't need to take care about time zones in this case. If you have just dates in format dd/MM/yyyy, when you will parse it with NSDateFormatter, it will use current timezone by default. So, when you will be comparing with your today's date all 3 dates will be in the same timezone and date/time adjusting will not be performed.
Related
I am having the following date and time 2013-04-25 10:42:44 +0000. When i convert the above date to string, i am getting the output as 2013-04-25 16:12:44. Following is the code i am using to convert the date to string
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init];
dateFormatter.timeZone = [NSTimeZone systemTimeZone];
[dateFormatter setDateFormat:#"yyyy-MM-dd HH:mm:ss"];
NSString *dateStr= [dateFormatter stringFromDate:date]];
NSLog(#"dateStr--%#",dateStr);
This gets asked over and over (but is difficult to find via search).
When you log an NSDate object, you will always get the date in UTC format. This is how the description method of NSDate is currently implemented.
As long as the difference you are seeing can be accounted for based on your local timezone relative to UTC, then what you are seeing it correct and expected behavior.
BTW - there is no reason to set the date formatter's timezone to the "system" timezone. This is already done by default. Same for the locale. Only set the timezone or locale if you want something different from the current values.
I guess it's a timezone issue. Set your formatters time zone to GMT:
dateFormatter.timeZone = [NSTimeZone timeZoneForSecondsFromGMT:0];
I assume the variable date gets initialized via [NSDate date].
Maybe the quite extensive answer in the follwing topic is helpful here, too.
Does [NSDate date] return the local date and time?
uidate picker has proper user zone set.
NSDate *date= Uidatepicker.date;
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateStyle:NSDateFormatterMediumStyle];
[dateFormatter setTimeZone:[NSTimeZone localTimezone]];
//show correct date and time
NSString *string=[dateFormatter stringFromDate:date];
//back to date
NSDate *outDate=[dateFormatter dateFromString:string];
The outdate is passed to another controller and eventually used to query db using time since 1970. The date used in the query has +4 hours (GMT time). I think it should have localtime. I know the NSdate has no timezone but I need the correct time for the db query. The db seems to have correct time since 1970 (based on local time). I am converting to string to check in this case as time is off by +4 hours.
Any suggestions and appreciate your help.
I am converting an NSString with a date format of 2012-06-30 into an NSDate using the following code:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"yyyy-MM-dd"];
NSDate *date = [dateFormatter dateFromString:dateString];
When omitting [dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]] the value in NSString is 2012-06-29 23:00:00 plus some automatically added time zone information, which indicates that the the system has some assumptions about the current time zone.
The conversion works fine when I set the time zone with the method above.
However, what would happen if the user is in a different time zone?
How can I make sure that iOS parses just the date as it is and does not add any time information?
The data will not change, timezones dont affect that date itself, it just affect the date presentation, so a date that says 13:00 GMT will have the same presentation of a date that is 14:00 GMT +1
You shouldnt care about the timezones, instead for date conversion to the current time zone of the device use
[dateFormatter setTimeZone:[NSTimeZone systemTimeZone]];
This will set the time zone of the device
I am trying to format a date object and I am noticing on the string I am passing in; 6 hours is being added to my time. This seems to be associating my date time object to GMT.
My code:
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"yyyy-MM-dd h:mm:ss a"];
[formatter setTimeZone:[NSTimeZone systemTimeZone]];
NSDate *date = [formatter dateFromString:#"2012-02-01 03:38:12 AM"];
NSLog(#"%#", date);
The result is:
2012-02-01 09:38:12 +0000
I have tried this with and without the setTimeZone and it does not matter. Any ideas on why this is displaying as GMT time?
Thanks,
Flea
The date that your formatter creates is not associated with any timezone, but the description method of NSDate (which is what NSLog uses for the output) converts any date to UTC. You would have to use another (or the same) date formatter's stringFromDate: method to print it with a different time zone.
All NSDates are absolute times, meaning that 3:00 AM central time in the United States is 9 AM UTC. I suspect that your systemTimeZone is central time in the United States.
NSLog always shows times in UTC.
If you want to see, as a string, what the time is in your time zone, then you can use the same date formatter stringFromDate: method, and make the you set the time zone of the date formatter to that time zone.
NSLog date formatting is an annoyance because it leads to the kind of confusion you are experiencing.
I run the following code:
NSDate *now = [NSDate date];
NSLog(#"now: %#", now);
and get :
2011-09-16 16:14:16.434 iSavemore[1229:7907] now: 2011-09-16 21:14:16 +0000
As you can see i'm running this at 16:14:16 (4:14 pm) but NSDate is returning 21:16:16 (9:14 pm!). Is this an Xcode4 issue or NSDate issue?
NSDate defaults to the Universal timezone (aka GMT).
I'm guessing you're somewhere on the East Coast, 5 hours behind UTC.
Try adding this to your date formatter...
NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setLocale:[NSLocale currentLocale]];
...and you should see your local time.
If you want to use a specified locale, rather than 'currentLocale', create a NSLocale for the relevant locale.
NSLocale *usLoc = [[NSLocale alloc] initWithLocaleIdentifier:#"en_US"];
[dateFormatter setLocale:usLoc];
...actually that's US (so possibly not Central).
More specific timezone help can be found here...
http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSDateFormatter_Class/Reference/Reference.html
However, if you want to show expiry time, wouldn't you still want it in the user's currentLocale?
If you look at the output you'll see that the log includes the timezone:
2011-09-16 16:14:16.434 iSavemore[1229:7907] now: 2011-09-16 21:14:16 +0000
^^^^^^
The time stamp of your log is local time. I assume you're in a timezone that is 5 hours ahead of UTC.
A NSDate refers to a particular point in time. It's up to you to display this however you want; usually with an NSDateFormatter.
This is the reason why you'll see plenty of recommendations against storing a time, or a date as anything other than an NSDate. If you try and store it as a string you'll run into a lot of trouble later on when trying to handle the display in different timezones.
Try setting the time-zone of your NSDate to one that is fitting your need, for example [NSTimeZone localTimeZone]
Just a wild guess here, but maybe it has something to do with time zones?