Check if time of NSDate object has passed - ios

Question

Im trying to check if the time of an NSDate has passed. Ive used the following but that obviously has the year so therefore it has passed. How would I check just the time of the NSDate object, only Hour and minutes are important:
NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
[dateFormat setDateFormat:#"HH:mm:ss"];
[dateFormat setLocale:[[NSLocale alloc] initWithLocaleIdentifier:#"en_US_POSIX"]];
NSDate *date = [dateFormat dateFromString:openingDay.endTime];
if ([date timeIntervalSinceNow] < 0.0) {
}
But the date is:
2000-01-01 5:30:00 p.m. +0000
The time string has the format 'HH:mm:ss'
I tried looking for the answer as I thought it would be common but no luck.
Edit:
I should have elaborated some more, I get a time from a server which is a string. I want to then check if this time is past. The string is an end time of a shops opening hours, I therefore want to check if the shop has closed.
Edit2:
the string I get from the Json object is end_time:17:30:00. I then want to check if the current time is after this time, if so, then show a closed UIAlertView. My approach was to take this string and turn it into a date object and compare it to the current time. However when I convert it to an NSDate object the year is 2000, which is obviously in the past. I hope I have provided enough.

Answer 1

To get the hour and minutes component, you do this:
NSDateComponents *components = [[NSCalendar currentCalendar] components:(NSCalendarUnitHour | NSCalendarUnitMinute) fromDate:date];
NSInteger hour = [components hour];
NSInteger minute = [components minute];
You can then create helper methods to keep the code organized:
- (NSInteger)hourFromDate:(NSDate *)date {
return [[NSCalendar currentCalendar] component:(NSCalendarUnitHour) fromDate:date];
}
- (NSInteger)minuteFromDate:(NSDate *)date {
return [[NSCalendar currentCalendar] component:(NSCalendarUnitMinute) fromDate:date];
}
note that component:fromDate:returns directly that component (as NSInteger), since it can only take one component type per parameter, while components:fromDate: returns a NSDateComponents, which then you can grab multiple components.
and then just:
NSDate *endDate = [dateFormat dateFromString:openingDay.endTime];
NSDate *today = [NSDate date];
NSInteger endDateHour = [self hourFromDate:endDate];
NSInteger endDateMinute = [self minuteFromDate:endDate];
NSInteger todayHour = [self hourFromDate:date];
NSInteger todayMinute = [self minuteFromDate:date];
BOOL hasEndMinutePassed = endDateMinute > todayMinute;
BOOL hasEndHourPassed = endDateHour > todayHour;
if ((hasEndHourPassed) || (endDateHour == todayHour && hasEndMinutePassed)) {
//Yep, it passed
} else {
//Nope, it didn't
}
I wrote it like this to keep things organized.
You could also write a category:
Header file:
#interface NSDate (Components)
- (NSInteger)hour;
- (NSInteger)minutes;
#end
Implementation file:
#import "NSDate+Components.h"
#implementation NSDate (Components)
- (NSInteger)hour {
return [[NSCalendar currentCalendar] component:NSCalendarUnitHour fromDate:self];
}
- (NSInteger)minute {
return [[NSCalendar currentCalendar] component:NSCalendarUnitMinute fromDate:self];
}
You can go a bit further than that and add the comparation logic inside the Category itself:
Adding this to the header:
- (BOOL)hourAndMinutesPassedFromDate:(NSDate *)date;
and then the implementation:
- (BOOL)hourAndMinutesPassedFromDate:(NSDate *)date {
BOOL hasEndMinutePassed = [self minute] > [date minute];
BOOL hasEndHourPassed = [self hour] > [date hour];
return ((hasEndHourPassed) || ([self hour] == [date hour] && hasEndMinutePassed));
}
Thats it. I didn't test the logic itself (but it should be accurate, i used something like this before), and of course you are free to modify this to fit your needs.