I'm trying to get the current date with :
NSLog(#"DATE NOW : %#", [NSDate date]);
But when I execute it, I have a difference of one hour between the date displayed and the current date.
Log http://data.imagup.com/12/1171458807.5637png
I found topics on questions like that but none of them gave me the answer.
How can I change that ?
You need to set the proper timezone. The default, as you can see, is UTC.
You can use a date formatter for doing that.
NSDateFormatter * dateFormatter = [[NSDateFormatter alloc] init];
NSTimeZone * timezone = [NSTimeZone timeZoneWithName:#"Europe/Rome"];
[dateFormatter setTimeZone:timezone];
[dateFormatter setTimeStyle:NSDateFormatterFullStyle
];
[dateFormatter setDateStyle:NSDateFormatterFullStyle];
NSLog(#"%#", [dateFormatter stringFromDate:[NSDate date]]);
For a list of available timezones you can use
NSArray *timeZoneNames = [NSTimeZone knownTimeZoneNames];
or check out the constants here on this Rails doc page.
Related
If I'm not interested in the time can I ignore it? I.e I have a date string that looks like this #"2012-12-19T14:00:00" but I'm only interested in getting the date (2012-12-19) but if I set NSDateFormatter like [dateFormatter setDateFormat:#"yyyy-MM-dd"]; it will return me a nil NSDate.
An NSDate object will always contain a time component as well, as it is representing a point in time — from this perspective one could argue the name NSDate is misleading.
You should create a date formatter for creating dates from string, set the time to the start of the day and use a second date formatter to output the date without time component.
NSString *dateString = #"2012-12-19T14:00:00";
NSDateFormatter *inputFormatter = [[NSDateFormatter alloc] init];
[inputFormatter setDateFormat:#"yyyy-MM-dd'T'HH:mm:ss"];
NSDateFormatter *outputFormatter = [[NSDateFormatter alloc] init];
[outputFormatter setDateStyle:NSDateFormatterShortStyle];
[outputFormatter setTimeStyle:NSDateFormatterNoStyle];
NSDate *date = [inputFormatter dateFromString:dateString];
//this will set date's time components to 00:00
[[NSCalendar currentCalendar] rangeOfUnit:NSDayCalendarUnit
startDate:&date
interval:NULL
forDate:date];
NSString *outputString = [outputFormatter stringFromDate:date];
NSLog(#"%#", outputString);
results in
19.12.12
while the format — as it is chosen by styling — will be dependent of your environment locale
all date string returns 10 characters for the date, what i mean is the date of todayy will be 2012-11-19
you can easily substring the date and use it as you want:
Example :
NSString* newDate = #"";
newDate = [[NSDate date]substringToIndex:10];
the out put will be : 2012-11-19
I'm working on an iPad app that speaks to a private PHP API that I built up to communicate to a database. This API has to transfer Three dates, a starting time, an end time and the current time.
I want to test if the current time is in-between the date range. So I took the times (like 16:50:00) and convert them into NSDates:
NSDateFormatter *former = [[NSDateformatter alloc] init];
[former setDateFormat:#"HH:mm:ss"];
[former setLocale:[NSLocale currentLocale]];
NSDate *fromDate = [former dateFromString:#"10:15:00"];
NSDate *nowDate = [former dateFromString:#"13:25:00"];
NSDate *toDate = [former dateFromString:#"16:30:00"];
When I'm now logging the dates by using NSLog(#"\n%#\n%#\n%#", fromDate, nowDate, toDate); I see that the locale is incorrect.
It seems as the NSDateFormatter just ignores the locale setting. I also logged the currentLocales identifier which is the right one ("de_DE" in my case"). The locale remains +0000.
How can I fix this issue? Thanks, with kind regards, Julian
Alright, I've removed the previous answer, try the following
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
NSTimeZone *zone = [NSTimeZone localTimeZone];
[formatter setTimeZone:zone];
[formatter setDateFormat:#"HH:mm:ss"];
NSDate *date = [formatter dateFromString:#"10:15:00"];
NSLog(#"Time %#",[formatter stringFromDate:date]);
I need to display the current Date and Time.
I have used ;
NSDate *currentDateNTime = [NSDate date];
I want to have the current date and time (Should display the system time and not GMT time).
The output should be in a NSDate format and not NSString.
for example;
NSDate *currentDateNTime = [NSDate date];
// Do the processing....
NSDate *nowDateAndTime = .....; // Output should be a NSDate and not a NSString
Since all NSDate is GMT referred, you probably want this:
(don'f forget that the nowDate won't be the actual current system date-time, but it's "shifted", so if you will generate NSString using NSDateFormatter, you will see a wrong date)
NSDate* currentDate = [NSDate date];
NSTimeZone* currentTimeZone = [NSTimeZone timeZoneWithAbbreviation:#"GMT"];
NSTimeZone* nowTimeZone = [NSTimeZone systemTimeZone];
NSInteger currentGMTOffset = [currentTimeZone secondsFromGMTForDate:currentDate];
NSInteger nowGMTOffset = [nowTimeZone secondsFromGMTForDate:currentDate];
NSTimeInterval interval = nowGMTOffset - currentGMTOffset;
NSDate* nowDate = [[NSDate alloc] initWithTimeInterval:interval sinceDate:currentDate];
Every moment in time is the same moment in time everywhere around the world —- it is just expressed as different clock times in different timezones. Therefore, you can't change the date to some other date that represents the time in your timezone; you must use an NSDateFormatter that you feed with the timezone you are in. The resulting string is the moment in time expressed in the clock time of your position.
Do all needed calculations in GMT, and just use a formatter for displaying.
Worth reading
Does [NSDate date] return the local date and time?
Some useful resources for anyone coming to this more recently:
Apple date and time programming guide do read it if you're doing anything serious with dates and times.
https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/DatesAndTimes/DatesAndTimes.html#//apple_ref/doc/uid/10000039i?language=objc
Useful category on NSDate with lots of utilities does allow a ~new~ date to be generated based on an existing date.
https://github.com/erica/NSDate-Extensions
There's also a swift version of the category
https://github.com/erica/SwiftDates
You need an NSDateFormatter and call stringFromDate this method to get a string of your date.
NSDateFormatter *dateformater = [[NSDateFormatter alloc] init];
[dateformater setDateFormat:#"yyyyMMdd,HH:mm"];
NSString *str = [dateformater stringFromDate: currentDateNTime];
use this method
-(NSDate *)convertDateToDate:(NSDate *) date
{
NSDateFormatter *formatter = [[[NSDateFormatter alloc] init] autorelease];
NSDate *nowDate = [[[NSDate alloc] init] autorelease];
[formatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
[formatter setDateFormat:#"yyyy-MM-d H:m:s"];
NSString * strdate = [formatter stringFromDate:date];
nowDate = [formatter dateFromString:strdate];
return nowDate;
}
this may return you what you want.
i hope you this may help you.
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
hi all
I am in India.And I have used the following code to get the current date.
[NSDate date]
it displaying the "2011-01-20 06:51:35 +0000" but actual time is "2011-01-20 12:21:35 +0000"
.Please tell me how to get the current date.
Thanks in advance
You need to use Date Formatter for this purpose.Below is the sample code for that.
NSDate *testDate=[NSDate date];
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"MM DD YY hh:mm"];//You can set your required format here
NSString *dt = [formatter stringFromDate:testDate];
[formatter release];
NSString *strDateTaken=dt;
Cheers
What does “actual time” mean? The current time in your time zone? Considering the time values given I’d guess that the first one is GMT and you want IST (+5:30). (See Time zones on Wikipeda.) Depends on what you want to do with the date – if you just want a formatted date and time in your current time zone, Aditya’s answer should work.
To Find Current date and difference between current date and Given date...its working code
NSDate *testDate=[NSDate date];
NSDateFormatter *formatterNew = [[NSDateFormatter alloc] init];
[formatterNew setDateFormat:#"dd-MM-yyyy HH:mm:ss "];
NSString *dt = [formatterNew stringFromDate:testDate];
NSString *strDateTaken=dt;
NSLog(#"Date=%#",strDateTaken);
[formatterNew release]; // This line can be removed if you are using ARC
NSDateFormatter *tempFormatter = [[[NSDateFormatter alloc]init]autorelease];
[tempFormatter setDateFormat:#"dd-MM-yyyy HH:mm:ss"];
NSDate *toDate = [tempFormatter dateFromString:strDateTaken];
NSLog(#"Current Date ==%#",toDate);
NSDateFormatter *tempFormatter1 = [[[NSDateFormatter alloc]init]autorelease];
[tempFormatter1 setDateFormat:#"dd-MM-yyyy HH:mm:ss"];
NSDate *startdate = [tempFormatter1 dateFromString:#"30-08-2011 16:25:00"];
NSLog(#"Last Date ==%#",startdate);
int i = [startdate timeIntervalSince1970];
int j = [toDate timeIntervalSince1970];
double X = j-i;
int days=(int)((double)X/(3600.0*24.00));
NSLog(#" Difference :%d",days);