Get last tuesday in month ios - ios

Question

Can get last weekday in the month through NSDateComponents? For example: last monday in month or last friday in month. etc

Answer 1

Just another way to solve. Find the first day of the next month, then search backwards for Tuesday.
let calendar = NSCalendar.currentCalendar()
let today = NSDate()
let components = calendar.components([.Year, .Month], fromDate: today)
components.month += 1
// If today is 2016-07-12 then nextMonth will be the
// first day of the next month: 2016-08-01
if let nextMonth = calendar.dateFromComponents(components) {
// Search backwards for weekday = Tuesday
let options: NSCalendarOptions = [.MatchPreviousTimePreservingSmallerUnits, .SearchBackwards]
calendar.nextDateAfterDate(nextMonth, matchingUnit: .Weekday, value: 3, options: options)
}

Answer 2

Here's a solution; tested, and fairly robust, I think.
We'll let NSCalendar walk through the month, a day at a time, and pull out all matching weekdays as NSDates. Then you can answer questions like, "The 3rd Wednesday of this month"
I believe the comments are clear about what is happening, and why.
If you need further clarification, I'll be happy to do so.
//What weekday are we interested in? 1 = Sunday . . . 7 = Saturday
NSInteger targetWeekday = 1;
//Using this methodology, GMT timezone is important to set
NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
calendar.timeZone = [NSTimeZone timeZoneWithAbbreviation:#"GMT"];
//set the components to the first of the current month
NSDateComponents *startComponents = [calendar components:NSCalendarUnitMonth | NSCalendarUnitYear fromDate:[NSDate date]];
startComponents.day = 1;
//the enumeration starts "afterDate", so shift the start back one day (86400 seconds) to include the 1st of the month
NSDate *startDate = [[calendar dateFromComponents:startComponents] dateByAddingTimeInterval:-86400];
//the enumeration searches for a match; we'll match at the midnight hour and find every occurance of midnight
NSDateComponents *dayByDay = [[NSDateComponents alloc] init];
dayByDay.hour = 0;
//I've opted to put all matching weekdays of the month into an array, so you can find any instance easily
__block NSMutableArray *foundDates = [NSMutableArray arrayWithCapacity:5];
[calendar enumerateDatesStartingAfterDate:startDate
matchingComponents:dayByDay
options:NSCalendarMatchPreviousTimePreservingSmallerUnits
usingBlock:^(NSDate *date, BOOL exactMatch, BOOL *stop){
NSDateComponents *thisComponents = [calendar components:NSCalendarUnitMonth | NSCalendarUnitWeekday fromDate:date];
//as long as the month stays the same... (or the year, if you wanted to)
if (thisComponents.month == startComponents.month) {
//does this date match our target weekday search?
if (thisComponents.weekday == targetWeekday) {
//then add it to our result array
[foundDates addObject:date];
}
//once the month has changed, we're done
} else {
*stop = YES;
}
}];
//Now, with our search result array, we can find the 1st, last, or any specific occurance of that weekday on that month
NSLog(#"Found these: %#", foundDates);
So, if you only wanted the last one, then just use [foundDates lastObject]

Answer 3

Try this code. This works for me.
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
NSDateComponents *comps = [gregorian components:NSWeekdayCalendarUnit fromDate:[NSDate date]];
int weekday = [comps weekday];
int lastTues;
int lastSatDay;
if (weekday==1) {
lastTues=5;
lastSatDay=1;
}
else if (weekday==2)
{
lastTues=6;
lastSatDay=2;
}
else if (weekday==3)
{
lastTues=7;
lastSatDay=3;
}
else if (weekday==4)
{
lastTues=1;
lastSatDay=4;
}
else if (weekday==5)
{
lastTues=2;
lastSatDay=5;
}
else if (weekday==6)
{
lastTues=3;
lastSatDay=6;
}
else if (weekday==7)
{
lastTues=4;
lastSatDay=7;
}
NSDate *lastTuesDay = [[NSDate date] addTimeInterval:-3600*24*(lastTues)];
NSDate *lastSaturday = [[NSDate date] addTimeInterval:-3600*24*(lastSatDay)];