CODEWITHSUNDEEP
iphoneobjective-ciosxcodensdate
pixelbitlabs
pixelbitlabs

Reputation: 1934

How to tell the amount of days from now until an NSDate?

How can I tell the amount of days from now until the date specified in my app? Here is what I have so far, but it comes up with "-30" every time, no matter what the date is:

NSDate * selected = [DatePicker date];
NSString * date = [selected description];

NSDateComponents *components = [[NSCalendar currentCalendar] components:NSDayCalendarUnit 
                                                              fromDate:DatePicker.date];

CalLabel1.text = [NSString stringWithFormat:@"%d", [components day]];

NSDateFormatter *temp = [[NSDateFormatter alloc] init];
[temp setDateFormat:@"dd/MM/yyyy"];
NSDate *stDt = [temp dateFromString:[temp stringFromDate:[NSDate date]]];
NSDate *endDt =  [temp dateFromString:[temp stringFromDate:[NSString stringWithFormat:@"%d", [components date]]]];
unsigned int unitFlags = NSMonthCalendarUnit | NSDayCalendarUnit;
NSCalendar *gregorian = [[NSCalendar alloc]
                         initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *comps = [gregorian components:unitFlags fromDate:stDt  toDate:endDt  options:0];
int days = [comps day];

NSLog(@"%i", [comps day]);

Upvotes: 3

Views: 2113

Answers (3)

lostAtSeaJoshua
lostAtSeaJoshua

Reputation: 1755

Swift 3 version of the accepted answer.

let dateComponents = Calendar.current.dateComponents([.day], from: fromDate, to: Date())

// number of days is an optional Int
if let daysCount = dateComponents.day {
    print(daysCount)
}

Upvotes: 1

anon
anon

Reputation: 

NSDate * selected = [DatePicker date];
NSCalendar *gregorian = [[NSCalendar alloc] 
                          initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *comps = [gregorian components: NSDayCalendarUnit 
                                       fromDate: [NSDate date]  
                                         toDate: selected  
                                        options: 0];
int days = [comps day];

NSLog(@"%i", [comps day]);

This calculates the number of days between now and the selected date. All your messing around with the date formatter was wrong and not necessary.

Upvotes: 7

Mark Adams
Mark Adams

Reputation: 30846

What about just using -timeIntervalSinceNow on NSDate?

NSDate *selectedDate = [datePicker date];
NSTimeInterval numberOfSecondsUntilSelectedDate = [selectedDate timeIntervalSinceNow];
NSInteger numberOfDays = numberOfSecondsUntilSelectedDate / 86400; // 86,400 seconds in a day

Upvotes: 3

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