My dateFromString is not working and i'm not sure why
NSString *purchase = #"2011-09-30 17:47:57";
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"yyyy-MM-dd hh:mm:ss"];
NSDate *date = [dateFormat dateFromString:purchase];
date is 'invalid CFStringRef'
See anything i might be overlooking?
Try changing the hours in the formatter to capitals, i.e. yyyy-MM-dd HH:mm:ss
I'm not sure if that will solve your error, but that is the correct way to parse a 24 hour time
in the format
"hh" means Hour [1-12].
"HH" means Hour [0-23].
See UTS Date Field Symbol Table for the date format specifiers.
Try this:
NSString *purchase = #"2011-09-30 17:47:57";
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"yyyy-MM-dd HH:mm:ss"];
NSDate *date = [dateFormat dateFromString:purchase];
Date Formatters Guide - HH is used for 24 hour times, hh for 12 hour.
If you mean that "date" is not accepted as an NSString by another function, that's because it's not a string, it's an NSDate.
(Where, precisely, are you getting the error message, and what is the full text?)
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 tried to convert String to date time and date time to string it's working but some what error. I not getting correct formate.
my excepting result should be:
like this.02/02/2013 05:24PM
time should be 12 hours formate;
NSString *dateTime = #"2013-02-02 15:54:31";
int time=[[temp objectForKey:#"created"]intValue];
NSLog(#"Time=%d",time);
// Convert string to date object
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"YYYY-MM-DD HH:MM:SS"];
[dateFormat setTimeZone:[NSTimeZone timeZoneWithName:dateTime]];
NSDate *date = [dateFormat dateFromString:dateTime];
NSLog(#"Nsdate=%#",date);
// Convert date object to desired output format
[dateFormat setDateFormat:#"hh:mma"];
dateTime = [dateFormat stringFromDate:date];
[dateFormat release];
NSLog(#"DateTime=%#",dateTime);
--------------------
NSLogs :
Time=2013
DateTime=2013-02-02 17:06:09
Nsdate=2013-01-02 11:30:00 +0000//it's not correct date
DateTime=02/01/2013 05:00PM//it's not correct date and time//
-------------
my excepting result should be like this:
DateTime :02/02/2013 05:24PM
If you have any idea please shear your ideas , It's will help me.
Change your this line
[dateFormat setDateFormat:#"YYYY-MM-DD HH:MM:SS"];
to
[dateFormat setDateFormat:#"YYYY-MM-dd HH:mm:SS"];
mm and dd should be small
Hope it helps you..
I must initialize an NSDate object from NSString in objective-c. I do it like this:
NSString *dateString = [[webSentence child:#"DateTime"].text stringByReplacingOccurrencesOfString:#"T" withString:#" "];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"yyyy-mm-dd HH:mm:ss"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"Europe/Budapest"]];
NSDate *date = [[NSDate alloc] init];
date = [dateFormatter dateFromString:dateString];
E.g: when I try it with string value #"2011-01-02 17:49:54" I get an NSDate 2011-01-02 16:49:54 +0000. As you can see there is a one hour difference between the two values. NSDate has a wrong value, it should be exactly the same I defined in my string in the timezone I set in dateFormatter. It seems it uses my date defined it string as UTC, even if I set its timezone to "Europe/Budapest". How can I fix this problem?
Thanks!
NSDate stores dates relative to a standard reference date. From the class docs:
"The sole primitive method of NSDate, timeIntervalSinceReferenceDate, provides the basis for all the other methods in the NSDate interface. This method returns a time value relative to an absolute reference date—the first instant of 1 January 2001, GMT."
NSDate does not itself have any concept of time zones. So the NSDateFormatter did the right thing: it converted a date which you told it had a GMT offset (by specifying a time zone), and gave you a "normalized" NSDate for that date.
If you want to see the date represented in the Europe/Budapest time zone, either use your existing date formatter (-stringFromDate:) or the appropriate NSDate description method (e.g. -descriptionWithCalendarFormat:timeZone:locale:).
P.S.- You don't need an alloc/init at all in your code as written. In non-ARC that would be a leak.
P.P.S.- Your date format is incorrect and giving nonsensical results. I've gone ahead and cleaned up your code as follows (tested under ARC):
NSString *dateString = #"2011-09-02 17:49:54";
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
NSTimeZone *tz = [NSTimeZone timeZoneWithName:#"Europe/Budapest"];
[dateFormatter setDateFormat:#"yyyy-MM-dd HH:mm:ss"];
[dateFormatter setTimeZone:tz];
NSDate *date = [dateFormatter dateFromString:dateString];
NSLog(#"%#", [dateFormatter stringFromDate:date]);
NSLog(#"%#", [date descriptionWithCalendarFormat:nil timeZone:tz locale:nil]);
Two things:
1) you have an error in your date format string. You should use MM for month, not mm (lowercase mm is for minutes)
2) after you create you NSDate object, you'll need to use the NSDateFormatter method stringFromDate: to generate a date string localized to a particular timezone. If you just do a straight NSLog() on the NSDate object it will show the date as GMT by default (GMT is one hour behind Budapest time)
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 want to ask 2 questions about the NSDate of iPhone application.
1) How to set the
NSDate *startDay to 01-01-2010 and NSDate *endDay to 31-12-2010
2) how many day between the startDay and the endDay.
What should I do? Thank you very much.
For handling dates with different formats you would need to use NSDateFormatter
NSDateFormatter *format = [[NSDateFormatter alloc] init];
[format setDateFormat:#"mm-dd-yyyy"];
To get date with specified format
NSString *dateString = [format stringFromDate:date];
To create a date from string with specified format:
NSDate *date = [format dateFromString:dateString];
NSDateFormatter documentation
To find the difference between two dates:
NSTimeInterval interval = [endDay timeIntervalSinceDate:startDay];
timeIntervalSinceDate documentation