Get current iPhone device timezone date and time from UTC-5 timezone date and time iPhone app?

Question

In my iPhone application i am very struggling to convert the webservice response time to current device time. The webservice time in UTC-5 timezone. The app is worldwide use app. So i have to convert the response time to current device timezone. This is simple messaging app.

When i have sent a message the time is "5:05 PM" (India Chennai timezone) but when am retrieve time from webservice is "2012-07-16 07:33:01". When i show the time in the app i should convert the time to device's local time. I have tried in some way but i can't solve yet. Code is:

NSDateFormatter *dateFormatter1 = [[NSDateFormatter alloc] init];  [dateFormatter1 setDateFormat:@"yyyy-MM-dd HH:mm:ss"];  [dateFormatter1 setLocale:[NSLocale currentLocale]]; //[dateFormatter1 setTimeZone:[NSTimeZone timeZoneWithName:@"IST"]]; [dateFormatters setTimeZone:[NSTimeZone systemTimeZone]]; NSDate *date = [dateFormatter1 dateFromString:dateStr]; NSLog(@"date : %@",date); 

But the output date and time is 2012-07-16 02:03:01 +0000 I have stored this date/time in Coredata and when I have retrieve from CoreData and covert to NSString using the below code,

NSDateFormatter *dateFormatters = [[NSDateFormatter alloc] init]; [dateFormatters setDateFormat:@"dd-MMM-yyyy hh:mm"]; [dateFormatters setDateStyle:NSDateFormatterShortStyle]; [dateFormatters setTimeStyle:NSDateFormatterShortStyle]; [dateFormatters setDoesRelativeDateFormatting:YES]; [dateFormatters setTimeZone:[NSTimeZone systemTimeZone]];   dateStr = [dateFormatters stringFromDate:dateString]; NSLog(@"DateString : %@", dateStr); 

The output date and time is "Today 7:33 AM". It should be show "Today 5:05 PM". Can anyone please save my day? Please help to solve this issue. Thanks in advance.

Answer 1

I have tested your scenario and added some code for your reference. Please test the below and please let me know it is useful for you.

NSString *dateStr = @"2012-07-16 07:33:01"; NSDateFormatter *dateFormatter1 = [[NSDateFormatter alloc] init];  [dateFormatter1 setDateFormat:@"yyyy-MM-dd HH:mm:ss"];  NSDate *date = [dateFormatter1 dateFromString:dateStr]; NSLog(@"date : %@",date);  NSTimeZone *currentTimeZone = [NSTimeZone localTimeZone]; NSTimeZone *utcTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"UTC"];  NSInteger currentGMTOffset = [currentTimeZone secondsFromGMTForDate:date]; NSInteger gmtOffset = [utcTimeZone secondsFromGMTForDate:date]; NSTimeInterval gmtInterval = currentGMTOffset - gmtOffset;  NSDate *destinationDate = [[[NSDate alloc] initWithTimeInterval:gmtInterval sinceDate:date] autorelease];  NSDateFormatter *dateFormatters = [[NSDateFormatter alloc] init]; [dateFormatters setDateFormat:@"dd-MMM-yyyy hh:mm"]; [dateFormatters setDateStyle:NSDateFormatterShortStyle]; [dateFormatters setTimeStyle:NSDateFormatterShortStyle]; [dateFormatters setDoesRelativeDateFormatting:YES]; [dateFormatters setTimeZone:[NSTimeZone systemTimeZone]];   dateStr = [dateFormatters stringFromDate: destinationDate]; NSLog(@"DateString : %@", dateStr); 

Thanks.

Answer 2

NSDate* currentDate = [NSDate date];  NSTimeZone* CurrentTimeZone = [NSTimeZone timeZoneWithAbbreviation:@"GMT"]; NSTimeZone* SystemTimeZone = [NSTimeZone systemTimeZone];  NSInteger currentGMTOffset = [CurrentTimeZone secondsFromGMTForDate:currentDate]; NSInteger SystemGMTOffset = [SystemTimeZone secondsFromGMTForDate:currentDate]; NSTimeInterval interval = SystemGMTOffset - currentGMTOffset;  NSDate* TodayDate = [[NSDate alloc] initWithTimeInterval:interval sinceDate:currentDate]; NSLog(@"Current time zone Today Date : %@", TodayDate); 

Swift 4

var currentDate = Date() var CurrentTimeZone = NSTimeZone(abbreviation: "GMT") var SystemTimeZone = NSTimeZone.system as NSTimeZone var currentGMTOffset: Int? = CurrentTimeZone?.secondsFromGMT(for: currentDate) var SystemGMTOffset: Int = SystemTimeZone.secondsFromGMT(for: currentDate) var interval = TimeInterval((SystemGMTOffset - currentGMTOffset!)) var TodayDate = Date(timeInterval: interval, since: currentDate) print("Current time zone Today Date : \(TodayDate)") 

Hope it helps to another developers ! Happy Coding !