i have a problem with method dateFromString, here is my code
NSString* res = [NSString stringWithFormat:#"%#/%#/%#",dateInput.text,monthInput.text,yearInput.text];
NSDateFormatter* formatter = [[NSDateFormatter alloc]init];
[formatter setTimeZone:[NSTimeZone localTimeZone]];
[formatter setDateFormat:#"dd/MM/yy"];
NSDate* inpTime = [formatter dateFromString:res];
[dateResult setText:[NSString stringWithFormat:#"%#",inpTime]];
when I run, the date in "inpTime" always is "dateInput" - 1.
for example: if "dateInput" is 5, the date in "inpTime" will be 4
You need to adjust the timezone.
Change
[formatter setTimeZone:[NSTimeZone localTimeZone]];
to
[formatter setTimeZone:[NSTimeZone timeZoneWithName:#"UTC"]];
This is because you're not setting the time, so it's set by default the midnight UTC.
But when you are displaying the date with a timezone other than UTC the time is shifted accordingly.
As an example if you live in New York the 12/29/2012 00:00:00 UTC is actually the 12/28/2012 18:00:00 for you.
You Code is perfect, no error what so ever.
Try nslogging dateInput.text, monthInput.text and yearInput.text...might be from here you are getting invalid data.
Related
I return a string from my database and value is '04/27/2016 1:16pm'. This value is already in UTC.
Now I want to convert that string to NSDATE, keeping it in UTC. When I try to convert string to date, the time is actually moving by 1 hour.
This is how I am doing it
NSString *tuploadtime = [tempDictionary valueForKey:#"uploadTime"];
//date conversions
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"MM-dd-yyyy HH:mm:ss a"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"UTC"]];
NSDate *duploadtime = [[NSDate alloc] init];
duploadtime = [dateFormatter dateFromString:tuploadtime];
NSLog(#"tuploadtime=%#, duploadtime=%#", tuploadtime, duploadtime);
the result is coming back as 2016-04-27 12:16:01 UTC.
result is
2016-04-27 10:12:44.612 x[1558:48608] tuploadtime=4/27/2016 2:10:33 PM, duploadtime=2016-04-27 12:10:33 +0000
basically the time is moving back 1 hour but I want to keep it the same.
hope I am making sense
Proper String Format for Date is most Important.
There are some methods to have HOURS format as follow with their differences..
kk: will return 24 format Hour in (01-24) hours will (look like 01, 02..24).
HH will return 24 format Hour in (00-23) hours will(look like 00, 01..23).
hh will return 12 format Hour (look like 01, 02..12).
so you should use your code like
NSString *tuploadtime = [tempDictionary valueForKey:#"uploadTime"];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"MM-dd-yyyy hh:mm:ss a"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"UTC"]];
NSDate *duploadtime = [[NSDate alloc] init];
duploadtime = [dateFormatter dateFromString:tuploadtime];
NSLog(#"tuploadtime=%#, duploadtime=%#", tuploadtime, duploadtime);
for More Date format refer this link
Your date format string is inconsistent:
[dateFormatter setDateFormat:#"MM-dd-yyyy HH:mm:ss a"];
HH means to use a 24-hour format. But then you also used a to indicate AM/PM. Using both is confusing the formatter and giving you off-by-one. You meant to use hh here.
I wrote a code block
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.locale = [NSLocale localeWithLocaleIdentifier:#"en_US"];
[dateFormatter setDateFormat:#"YYYY-MM-dd"];
NSLog(#"date:%#,string:%#", aDate,[dateFormatter stringFromDate:aDate]);
it works well for most date, but if the date is 2013-12-30 it works strange .
the Log string is date:2013-12-30 16:00:00 +0000,string:2014-12-31
Why? why the date 2013-12-30 convert to string is 2014-12-31?
The NSDate you're giving it is 4pm in GMT. You're probably not in GMT, so it's formatting that time/date for your current timezone, where it's at least eight hours later.
Create your NSDate with the local timezone, or use NSDateComponents if you really want just a date with no time.
This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
How to determine if locale's date format is Month/Day or Day/Month?
I've struggled some time now and I'm stuck! I either need a local formatted pattern date string in the form "mm-dd-yyyy" or "08-25-2012". How should I do this? Use dateFormat? Please help me!
NSDateFormatter has a convenience class method:
[NSDateFormatter localizedStringFromDate:date dateStyle:NSDateFormatterShortStyle timeStyle:NSDateFormatterNoStyle];
You can specify NSDateFormatterNoStyle,..ShortStyle,..MediumStyle, or..LongStyle
You can use NSDateFormatter with MM-dd-yyyy and then use NSTimeZone applied to the formatter to adjust for the local time zone.
This:
NSDate *date = [[NSDate alloc] init];
NSLog(#"%#", date);
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"MM-dd-yyyy hh:mm"];
NSString *dateString = [dateFormatter stringFromDate:date];
NSLog(#"%#", dateString);
NSTimeZone *timeZone = [NSTimeZone localTimeZone];
[dateFormatter setTimeZone:timeZone];
NSLog(#"adjusted for timezone: %#", [dateFormatter stringFromDate:date]);
Outputs:
2012-08-26 08:30:53.741 Craplet[2585:707] 2012-08-26 12:30:53 +0000
2012-08-26 08:30:53.742 Craplet[2585:707] 08-26-2012 08:30
2012-08-26 08:30:53.743 Craplet[2585:707] adjusted for timezone: 08-26-2012 08:30
I am loading in dates from my web service, I'm sending dates in the format (GMT times): 02/11/11 10:56:09
I am creating an NSDate form this using NSDateFormatter as such:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd/MM/yyyy HH:mm:ss"];
NSDate *journeyDate = [dateFormatter dateFromString:str];
[dateFormatter release];
This works great, after I'm comparing this to the current date to get relative time intervals.
The problem is when the phone is set up in a different timezone, when I load in the date from my api, and use the date formatter, what seems to be happening is the phone is assuming the date string is local time and it's converting it to GMT.
Example:
I load in a date with the time 10am from the api.
The phone is set to PDT.
The date formatter is creating an NSDate assuming that my date string with 10am, is actually relevant to the phone.
I end up with a date and time equal to 5pm, adding 10 hours.
I am trying to specify in my date formatter that the string is GMT, but I'm having trouble, I've tried the following, adding GMT to the format:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd/MM/yyyy HH:mm:ss GMT"];
NSDate *journeyDate = [dateFormatter dateFromString:str];
[dateFormatter release];
This is not working.
Can anyone give any advice ?
Solution
Just a recap, I got it working with a terrible work around by appending GMT to the original string, and formatting that:
NSString * cheat = [NSString stringWithFormat:#"%# GMT", str];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd/MM/yyyy HH:mm:ss zzzz"];
NSDate *journeyDate = [dateFormatter dateFromString:cheat];
[dateFormatter release];
return journeyDate;
This was a kind of unstable hack, because if the string changed to include a timezone, it wouldn't work anymore. For anyone who needs to do as myself, the following is just a quick example on how to create an NSTimeZone.
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd/MM/yyyy HH:mm:ss"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"UTC"]];
NSDate *journeyDate = [dateFormatter dateFromString:str];
[dateFormatter release];
return journeyDate;
Thanks for the quick help.
I suspect you just want to use NSDateFormatter.setTimeZone to force it to use UTC. You don't want to change the format string because presumably the string doesn't include the letters "GMT" - instead, you want to change which time zone the string is interpreted in, which is what setTimeZone will do.
You should use the setTimeZone method: http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSDateFormatter_Class/Reference/Reference.html
i would like to create a tableView with different name of cities, and by clicking on each we can have the current time, i was thinking that i could put the GMT time and change it depending on the cell (the name of the city) we clicked : and thus, add +2 to the GMT hour, or -6 to the GMT. Do you think this could be possible?
I have this code for now, but i'm looking for some advices to create the "+2" or "-6" to this code : (this code is located in a method, updated every second to have the hour-minute-second updated)
NSDate *myDate = [NSDate date];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:#"GMT"]];
[dateFormatter setDateFormat:#"dd-MM-YYYY"];
NSString *GMTDateString = [dateFormatter stringFromDate: myDate];
[dateFormatter release];
Thanks for your help
So, you want do display current time in different time zones?
You can pass different time zones to dateFormatter and it'll convert date to that time zone and return it to you.
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:#"GMT"]];
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:3600*2]]; // GMT+2
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:-3600*6]]; // GMT-6
Use the date formatter for this. You just set the timezone and then you can get correct dates.
//-6 hours
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:-21600]];
//+2 hours
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:7200]];
If you would like to account for Daylight Savings use a named time zone instead of -6.