I'm new to iPhone development. I want to set default date to NSDate Object as string. I don't see any easy way or method...
I think there might be a method in NSCalender? If there's such a method, please tell me.
Thanks in advance.
I'm not totally clear on what you are asking, but to create an instance of an NSDate object with the current date, one calls:
NSDate * myDate = [NSDate date];
If you are saying that you have a c-string or NSString that needs to be parsed to initialize an NSDate object, that's another question.
I have some code posted here:
How get a datetime column in SQLite with Objective C
that shows how to create NSDates from NSStrings using NSDateFormatter.
If you want to create an NSDate from a string, you need to use an NSDateFormatter to do it. It's important to note that the formatter will use the current locale's time zone when constructing the date, unless you put a time-zone in as part of the format. For more information about constructing time zones, see NSTimeZone.
For example, to create a date using the ubiquitous format '2011-01-16 00:00' in UTC, you would do:
NSDateFormatter* formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"yyyy-MM-dd HH:mm"];
// Only certain abbreviations are okay, like UTC. See docs for more info
[formatter setTimeZone:[NSTimeZone timeZoneWithAbbreviation:#"UTC"]];
NSDate* midnight_26_jan_2011_utc = [formatter dateFromString:#"2011-01-26 00:00"];
// this will display in your system locale
// (for me, it shows 2011-01-25 19:00 +0500 because I'm America/New_York time)
NSLog(#"date: %#", midnight_26_jan_2011_utc);
[formatter release];
Edit: Added time to format string.
You will need to look at the NSDate and NSDateFormatter classes. Here's a simple example of how to use them:
NSString* defaultDateString = [NSString stringWithFormat:#"2011-01-22 15:30:00"];
NSDateFormatter* dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"yyyy-MM-dd HH:mm:ss"];
NSDate* defaultDate = [dateFormatter dateFromString:defaultDateString];
[dateFormatter release];
and if you wanted to get the string from a date you can just use:
NSString* defaultDateString = [dateFormatter stringFromDate:defaultDate];
NSDateFormatter *DateFormatter=[[NSDateFormatter alloc] init];
[DateFormatter setTimeZone:[NSTimeZone defaultTimeZone]];
[DateFormatter setDateFormat:#"yyyy-MM-dd hh:mm:ss"]; //here,you can set the date format as you need
NSDate *now = [[[NSDate alloc] init]autorelease];
NSString *theDate = [DateFormatter stringFromDate:now];
Now, you can use the string the date. :)
NSDateFormatter *dateFormatter = [[[NSDateFormatter alloc]init]autorelease];
[dateFormatter setDateFormat:#"yyyy-mm-dd"];
NSDate *yourDate = [dateFormatter dateFromString:#"2011-01-26"];
Related
in my iPhone application I need to convert NSString to NSDate with formaT. Here is my code:
+(NSDate*)dateFromJsonString:(NSString*)string{
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"yyyy'-'MM'-'dd'T'HH':'mm':'ss'"];
NSLog(#"%#", [dateFormat dateFromString:string]);
return [dateFormat dateFromString:string];
}
If parameter "string" is 2013-05-30T15:53:02 after converting - [dateFormat dateFromString:string] it becomes 2013-05-30 12:53:02 +0000 , so there is a difference in 3 hours. How can I fix it?
You need to set the correct time zone. Here is a sample, correct it to the time zone of your server:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
dateFormatter.timeZone = [NSTimeZone timeZoneWithAbbreviation:#"UTC"];
[dateFormatter setDateFormat:#"yyyy'-'MM'-'dd'T'HH':'mm':'ss'"];
return [dateFormatter dateFromString:dict[#"completed_at"]];
EDIT: You can check the available time zones with a class method on NSTimeZone:
+ (NSArray *)knownTimeZoneNames
Just output it to the console, and choose the time zone that corresponds to the server one.
EDIT 2: Probably this is more useful:
+ (NSDictionary *)abbreviationDictionary
Choose your time zone and than just change the #"UTC" in the code above with the desired abbreviation.
Try this dateFormat. Since timezone is not given in dateString, dateFormatter assumes it to be local timezone. If you know the timezone set it to formatter.
[dateFormat setDateFormat:#"yyyy-MM-dd'T'HH:mm:ss"];
Check this answer for more details.
This is TimeZone issue so use this code to fix this problem :
+(NSDate*)dateFromJsonString:(NSString*)string
{
NSLocale *locale = [[NSLocale alloc] initWithLocaleIdentifier:#"en-US"];
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"yyyy'-'MM'-'dd'T'HH':'mm':'ss'"];
[dateFormat setLocale:locale];
[dateFormat setTimeZone:[NSTimeZone systemTimeZone]];
NSLog(#"%#", [dateFormat dateFromString:string]);
return [dateFormat dateFromString:string];
}
Hope it helps you.
You can use the following code to set timezone.
[dateFormatter setTimeZone:[NSTimeZone systemTimeZone]];
But before you try that, i should tell you that if you are logging the date, it will show it in UTC format and not in the timezone of your computer. So dont check your date by printing it. So try converting the date to string and printing it to check if the date is correct or not.
Try logging NSLog(#"%#",[dateFormatter stringFromDate:date]); first
You just need to set current time zone for date formatter. Because of it, you got some time difference. Use below code..
+(NSDate*)dateFromJsonString:(NSString*)string
{
NSDateFormatter *inputFormatter = [[NSDateFormatter alloc] init];
[inputFormatter setTimeZone:[NSTimeZone defaultTimeZone]];
[inputFormatter setDateFormat:#"YYYY-MM-dd'T'HH:mm:ss"];
NSDate *xExpDate = [inputFormatter dateFromString:string];
return xExpDate;
}
I am using following code to generate NSDate -> NSString
+(NSString *)getCurrentTime
{
NSDate *now = [NSDate date];
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd-MM-yyyy hh:MM:SS a"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
NSString* str =[dateFormatter stringFromDate:now];
[dateFormatter release];
NSLog(#"%#",str);
return str;
}
everything is fine in above code. I am using above code to store string in Database. Now while retrieving that string gives me NULL. Following is my code to retrieve date in specific format
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"hh:MM:SS a"];
[dateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
NSDate *dt =[dateFormatter dateFromString:crdInfo.swipeTime];
NSLog(#"Date : %#",dt);
[dateFormatter release];
How should I retrieve or store with particular format?? My crdInfo.swipeTime is retrieving String propertly...
First off, why not just store the NSDate object or epoch timestamp? This will give you much more flexibility in the future.
Now to your problem, I suspect it is due to your configuration of the NSDateFormatter, you're saving it in one format and trying to convert it to a date using a different format. Make the formats the same and try again. If you want to display it differently than it is stored you're likely going to need to convert it to and NSDate using the stored format and then again use another date formatter to get it in the format you want it as a string.
As Narayana suggested you need to retrieve the date with same format as you have stored. Retrieve it as below : -
NSDateFormatter *reDateFormatter = [[NSDateFormatter alloc] init];
[reDateFormatter setDateFormat:#"dd-MM-yyyy hh:MM:SS a"];
[reDateFormatter setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
NSDate *dt = [reDateFormatter dateFromString:str];
NSLog(#"The Date : %#",dt);
[reDateFormatter setDateFormat:#"hh:MM:SS a"];
NSString *currentTime = [reDateFormatter stringFromDate:dt];
NSLog(#"%#",currentTime);
Hope it helps you.
Try to format it to dd-MM-yyyy hh:mm:ss a.
You wrote dd-MM-yyyy hh:MM:SS a where MM in hh:MM:SS gives month which is unrecognized in this format and there is no point writing upercase SS for seconds
Hope you understand it.
I'm working on an assignment that allows the user to display events that are happening 'today'. I have parsed the XML file and stored the contents into an array. The contents of the XML file consists of a title, description, date etc. The dates are in NSString format and I want to convert them into NSDates and compare them with today's date before displaying them in a UITableView.
I'm new to obj-c and I've searched online for help on NSDate, but I couldn't find what I need. Any links, advice or help on this is really appreciated. Thanks in advance (:
suppose dateString contains the date in string format
first get date from string:-
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"dd/mm/yyyy"];
NSDate *dateprevious = [formatter dateFromString:dateString];
Now get today date
NSDate *date=[NSDate date];
[formatter setDateFormat:#"dd"];
NSString *dateOfGame =[formatter stringFromDate:dateprevious];
NSString *todaydate =[formatter stringFromDate:date];
[formatter release];
if([todaydate isEqualToString:dateknown])
{
NSLog(#"date matched");
}
Depending on the format of the string, you can use this:
+ (id)dateWithNaturalLanguageString:(NSString *)string
To compare two dates you will find here a lot of usefull answers :)
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:#"dd-MM-yyyy , hh:mm a"];
[dateFormatter setDateStyle:NSDateFormatterLongStyle];
NSDate *date = [[dateFormatter datefromString:date] retain];
[dateFormatter release];
You can use this one
Have a look at NSDateFormatter
It has a method called dateFromString
Like you could do the following:
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"dd/mm/yyyy"];
NSDate *date = [formatter dateFromString:#"5/5/2011"];
I have this string...
2010-08-24T16:00:00-05:00
and I'd like to extract the time portion from it (i.e. 16:00) and convert it to its 12-hour equivalent (i.e. 04:00 pm). I'm trying to use NSDateFormatter to accomplish this, but it's not working...
NSDateFormatter* dateformatter = [[NSDateFormatter alloc] init];
[dateformatter setDateFormat:#"hh:mm a"];
NSDate *date1 = [dateformatter dateFromString:[listOfTimes objectAtIndex:0]];
[dateformatter release];
Can I use NSDateFormatter with this date format? If not, how can I extract the time and convert it to its 12-hour time equivalent?
Thanks!
The problem has to do with parsing the colon. I asked the same question and the solution is here: How to parse a date string into an NSDate object in iOS?
I think you should be able to do something like the following.
// create the date formatter object
NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
[formatter setDateFormat:#"yyyy-MM-dd'T'HH:mm:ss"];
NSDate* date = [formatter dateFromString:dateString];
// set up the new date format
[formatter setDateFormat:#"hh:mm:ss"];
NSString *twelveHourTime = [formatter stringFromDate:date];
[formatter release];
Update: Fixed the dateFormatter string format. I had the line below, but the Z seems to be unnecessary. Timezones always screw me up. :-/
[formatter setDateFormat:#"yyyy-MM-dd'T'HH:mm:ssZ"];
This answer needs to be updated. As of iOS 10 the system provided NSISO8601DateFormatter is available for this particular format.
I am pulling data from an RSS Feed. One of the keys in the feed is is a string representing the date and time the item was created.
I am trying to convert this string value to an NSDate. The string value is returned from the RSS feed as: 2009-11-18T22:08:00+00:00
I tried the following code to no avail:
NSDateFormatter *df = [[NSDateFormatter alloc] init];
[df setDateFormat:#"yyyyMMdd HH:mm"];
NSDate *myDate = [df dateFromString: [[storedDates objectAtIndex:indexPath.row] objectForKey: #"UsersDate"]];
Ideally; on top of converting the value to a NSDate value, I would also like to format it using the localised date format on the handset.
Any pointers would be a great help.
Kind Regards
To retrieve the dateFormat:
NSDateFormatter *df = [[NSDateFormatter alloc] init];
[df setDateFormat:#"yyyy-MM-dd'T'HH:mm:ssZ"];
NSDate *myDate = [df dateFromString: [[storedDates objectAtIndex:indexPath.row] objectForKey: #"UsersDate"]];
You can use the predefined formats if you would like to format time and date according to the user's locale:
NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateStyle:NSDateFormatterShortStyle];
[dateFormatter setTimeStyle:NSDateFormatterLongStyle];
NSLog(#"%#",[dateFormatter stringFromDate:someDate]);
[dateFormatter release]; // don't forget to release the dateformatter
Check the documentation to see which formatter suits you best.
Actually date form in RSS feed may differ, so best way to parse it is following
[NSDate dateFromInternetDateTimeString:processedText formatHint:DateFormatHintRFC822];
This is not a standard function, library for it can be found here https://gist.github.com/953664