How to skip time in NSDate?

Question

I want to get difference between dates skipping time means if one date is 13 Jan 2012 - 11 pm and other date is 14 Jan 2012 - 12 am,then difference should be 1 day not 0 day.I mean I want difference between date only, 14 Jan 2012 - 13 Jan 2012, skipping time. I know I can use NSDate api to calculate difference but the problem is it consider time also.So I thought while calculating difference I will skip time but I do not know how to skip time because if I use NSDateFormatter it will return string not date.Please help me what I can do?

Thanks in advance!

Answer 1

What you need to do is get the NSDateComponents of each date first. Once you do that you can compare the 'day' component to get you difference.

NSCalendar *cal = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
[cal setTimeZone:[NSTimeZone timeZoneForSecondsFromGMT:0]];
NSDate *date1 = ....;
NSDate *date2 = ....;
NSDateComponents *comps1 = [cal components:NSDayCalendarUnit|NSYearCalendarUnit|NSMonthCalendarUnit fromDate:date1];
NSDateComponents *comps2 = [cal components:NSDayCalendarUnit|NSYearCalendarUnit|NSMonthCalendarUnit fromDate:date2];

date1 = [cal dateFromComponents:comps1];
date2 = [cal dateFromComponents:comps2];

NSDateComponents *diffComps = [cal components:NSDayCalendarUnit fromDate:date1 toDate:date2 options:0];

NSLog(@"Days diff = %d", diffComps.day);

The date API can be kind of weird to wrap your head around, but once you do it is quite powerful.