how to find days remaning in birthdate [duplicate] - ios

Question

This question already has answers here:
Calculate number of days remaining [duplicate]
(5 answers)
Closed 8 years ago.
i want to remaning days from array of birthdates im using following code for it
for(int i =0;i<_convertedBdates.count;i++){
NSDateFormatter *tempFormatter = [[NSDateFormatter alloc]init];
[tempFormatter setDateFormat:#"dd/MM/YYYY"];
NSDate *firstdate = [tempFormatter dateFromString:[_convertedBdates objectAtIndex:i]];
NSString *curYear = [tempFormatter stringFromDate:[NSDate date]];
NSDate *secondDate = [tempFormatter dateFromString:curYear];
NSTimeInterval lastDiff = [firstdate timeIntervalSinceNow];
NSTimeInterval todaysDiff = [secondDate timeIntervalSinceNow];
NSTimeInterval dateDiff = lastDiff - todaysDiff;
int day = dateDiff/(3600*24);
NSLog(#" _newlymadeArray %#",[_convertedBdates objectAtIndex:i]);
NSLog(#" days %d",day);
[_daysremaining addObject:[NSString stringWithFormat:#"%d",day] ];
}
NSLog(#" days %#",_daysremaining);
what wrong i am doing why i am not getting correct days

Answer 1

for(int i =0;i<_convertedBdates.count;i++){
NSDateFormatter *tempFormatter = [[NSDateFormatter alloc]init];
[tempFormatter setDateFormat:#"dd/MM/YYYY"];
NSDate *firstdate = [tempFormatter dateFromString:[_convertedBdates objectAtIndex:i]];
NSString *curYear = [tempFormatter stringFromDate:[NSDate date]];
NSDate *secondDate = [tempFormatter dateFromString:curYear];
NSTimeInterval lastDiff = [firstdate timeIntervalSinceNow];
NSTimeInterval todaysDiff = [secondDate timeIntervalSinceNow];
NSTimeInterval dateDiff = lastDiff - todaysDiff;
int day = dateDiff/(3600*24);
day = day -1;
NSLog(#" _newlymadeArray %#",[_convertedBdates objectAtIndex:i]);
NSLog(#" days %d",day);
[_daysremaining addObject:[NSString stringWithFormat:#"%d",day] ];
}
NSLog(#" days %#",_daysremaining);

Answer 2

try like this it will help you,
NSString *start = #"03/12/2013";
NSString *end = #"09/12/2013";
NSDateFormatter *f = [[NSDateFormatter alloc] init];
[f setDateFormat:#"dd/mm/yyyy"];
NSDate *startDate = [f dateFromString:start];
NSDate *endDate = [f dateFromString:end];
NSCalendar *gregorianCalendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *components = [gregorianCalendar components:NSDayCalendarUnit
fromDate:startDate
toDate:endDate
options:0];
NSLog(#"%d",[components day]);

Answer 3

Keep your code simple :
You can use a method and call it within your calculation block:
- (NSInteger)daysBetweenDate:(NSDate*)fromDateTime andDate:(NSDate*)toDateTime{
NSDate *fromDate;
NSDate *toDate;
NSCalendar *calendar=[NSCalendar currentCalendar];
[calendar rangeOfUnit:NSDayCalendarUnit startDate:&fromDate interval:NULL forDate:fromDateTime];
[calendar rangeOfUnit:NSDayCalendarUnit startDate:&toDate interval:NULL forDate:toDateTime];
NSDateComponents *difference = [calendar components:NSDayCalendarUnit
fromDate:fromDate toDate:toDate options:0];
return [difference day];
}