I am trying to convert the following string into an NSDate object:
NSString *str=#"25 May 2012 10:25:00";
NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc] init] autorelease];
[dateFormatter setDateFormat:#"d MMM yyyy HH:mm:ss"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"asia/kolkata"]];
NSDate *date = [dateFormatter dateFromString:str];
In console : date-->2012-05-25 04:55:00 +0000....it lags behind 5 hours and 30 minutes and assumes GMT timezone instead of Asia...Why it is so?
When you see an [NSDate description] printed in the console, it is always the corresponding time in GMT. If you use the same date formatter to convert the date back to a string, it should be in the specified time zone.
An [NSDate description] is what you see if you type
po date
or
po [date description]
or you use NSLog to send either one of these forms to the console.
if you are looking for India Timezone you should use:
Related
I have to convert this NSString: "12/13/1980" to a NSDate object.
I use a code like this:
NSString *birthday = #"12/13/1980"
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"MM/dd/yyyy"];
NSDate *date = [dateFormat dateFromString:dateString];
But the result is this: "1980-12-12 23:00:00 +0000"
Why? I'd like the same format and the same date.
Thank you very much.
The [dateFormat dateFromString:dateString] method produces an NSDate object which represents a single point in time.
When you NSLog a date object, it is printing a system representation of the NSDate object. I'm assuming your locale is GMT+1 .. so the NSLog prints 12/12/1980 23:00.
If you want to print the date object back, use your formatter to do [dateFormat stringFromDate:date];
It's because a NSDate object has always to have a time and a timezone, so if you don't specify that in your the string you're trying to convert IOS will use your local timezone and then guess the time, wich in this case will be 23:00 in UTC 0
The format is dependent on the localisation, there's also the option to set whether the date/time is short, medium or long format - I believe short is what you're looking for:
[dateFormatter setDateStyle:NSDateFormatterShortStyle];
[dateFormatter setTimeStyle:NSDateFormatterNoStyle];
https://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSDateFormatter_Class/Reference/Reference.html
This question already has an answer here:
NSDateFormatter not giving me correct
(1 answer)
Closed 9 years ago.
this is the code that i am using for changing date formate
NSLog(#"newBirthDates%#",_newwBirthDates);
NSDateFormatter *Form = [[NSDateFormatter alloc] init];
[Form setDateFormat:#"MM/dd"];
NSDate *date1 =[NSDate date];
NSString *string =[Form stringFromDate:date1];
NSLog(#"string%#",string);
NSDate *todaydate =[Form dateFromString:string];
NSLog(#"todaydate%#",todaydate);
this is what i get as output
newBirthDates(
"05/22",
"07/11",
"10/07",
"02/20"
)
newBirthDates(
"05/22",
"07/11",
"10/07",
"02/20"
)
string03/18
todaydate1970-03-17 18:30:00 +0000
now my question is why 3/18 become 03/17?? why one day get decreases
The answer is simple - time zones.
Take a close look at what NSLog prints out
1970-03-17 18:30:00 +0000
By default, a NSDateFormatter is set to your local timezone. That means, if your time zone is +5:30 giving it a date "1970/18/3" results in 1970-03-18 00:00:00 +0530.
However, NSLog always prints dates in GMT (zero) time zone, adding/substracting the time zone difference (5 hours and 30 minutes).
Basically, there is nothing to fix, you just have to understand how NSLog works if you want to use it to check NSDate values.
Your Log is showing as per string value, eliminating all important timezone differences.
Log of NSDate shows you the time from GMT.
And both the values are correct.
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.
You must read NSDate Documentation.
for getting correct date you can use this one,
NSDateFormatter *Form = [[NSDateFormatter alloc] init];
[Form setDateFormat:#"MM/dd"];
[Form setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
NSDate *date1 =[NSDate date];
NSString *string =[Form stringFromDate:date1];
NSLog(#"string%#",string);
NSDate *todaydate =[Form dateFromString:string];
NSLog(#"todaydate%#",todaydate);
above code will give the correct date.
The Main thing is TimeZone : [Form setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
This is the Correct Code :
NSDateFormatter *Form = [[NSDateFormatter alloc] init];
[Form setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
[Form setDateFormat:#"MM/dd"];
NSDate *date =[NSDate date];
NSString *string =[Form stringFromDate:date];
NSDate *todaydate = [Form dateFromString:string];
NSLog(#"todaydate %#",todaydate);
I want to save a date object to the backend of my App. This is the code:
NSDate *date = self.birthPickerView.date;
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"YYYY-MM-dd HH:mm:ss"];
NSString *stringFromDate = [formatter stringFromDate:date];
NSLog(#"%#", stringFromDate);
NSDate *endDate = [formatter dateFromString:stringFromDate];
[formatter release];
NSLog(#"%#", endDate);
// Save to database
[user setObject:endDate forKey:#"birth"];
This is the print out result:
1985-03-05 00:00:00
1985-03-04 23:00:00 +0000
The end date is not right. I want to save 1985-03-05 in the database. Can you help me what is wrong?
Edit
[self.birthPickerView setTimeZone:[NSTimeZone localTimeZone]];
NSLog(#"%#", self.birthPickerView.date);
NSLog(#"%#", self.birthPickerView.timeZone);
[user setObject:self.birthPickerView.date forKey:self.navTitle];
This code save 1984-03-04 23:00:00 in database. what is wrong with it?
I don't see why would you need to convert your date into a string, and then back into the date again.
However, I'm pretty sure this happens because you didn't set the timezone on your NSDateFormatter. The default time zone is GMT which might cause the time offset you see there.
NSLog(#"%#", self.departDate);
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"MM/dd/yyyy"];
NSLog(#"%#", [dateFormat stringFromDate:self.departDate]);
[dateFormat release];
So I have this code, which returns this in the console:
2011-06-09 00:00:00 +0000
06/08/2011
Any ideas why this is happening? As you can see, my self.departDate object returns 2011-06-09 as it's date. When I try to use date formatter to convert, I lose a day WTF?
The first log corresponds to a GMT date. However when you create an NSDateFormatter instance, it will have a default timezone set to the user's timezone which I am guessing is probably somewhere west of Greenwich. If you want the time to remain in GMT, you will have to add this line,
[dateFormat setTimeZone:[NSTimeZone timeZoneWithName:#"GMT"]];
I want current date and time in PST. I used this code
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"yyyy-MM-dd HH:mm:ss zzz"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneWithName:#"PST"]];
NSString *timeStamp = [dateFormatter stringFromDate:[NSDate date]];
NSLog(#"String:%#",timeStamp);
It returns correct date and time in PST in string form but I want NSDate in PST. So when I change NSString to NSDate like this:
NSDate *currentPST = [dateFormatter dateFromString:timeStamp];
NSLog(#"currentPST Date:%#",currentPST);
It returns date in GMT. I have done R&D but all in vain.Output is:
String:2011-05-18 22:28:54 PDT
currentPST Date:2011-05-19 05:28:54 +0000
Can anyone suggest a solution please.
Thanks in advance
In Cocoa, NSDate is an abstract representation of a date with no time zone information applied.
Whenever you print a NSDate object, it will print the date value corresponds to the default timezone(your device timezone). Your device timezone is GMT thats why you get the value like that. If you look into that deeply, both the time where same, but the timezone varies.