How to get the number of weeks in a month

Question

Here is the problem, i'm looking for a way to get the number of weeks in a month. I already find a solution that seems to work on ios 5, but it not on io6 (number returned is not the same, one more on ios 6).

- (int)weeksOfMonth:(int)month inYear:(int)year
{
    NSCalendar *cCalendar = [NSCalendar currentCalendar];

    NSDateComponents *components = [[NSDateComponents alloc] init];
    [components setMonth:month];
    [components setYear:year];

    NSRange range = [cCalendar rangeOfUnit:NSDayCalendarUnit
                               inUnit:NSMonthCalendarUnit
                              forDate:[cCalendar dateFromComponents:components]];

    cCalendar = [NSCalendar currentCalendar];
    [cCalendar setMinimumDaysInFirstWeek:4];

    NSDateFormatter *dateFormatter = [[NSDateFormatter alloc]init];
    [dateFormatter setLocale: [[NSLocale alloc] initWithLocaleIdentifier:@"fr"]];
    [dateFormatter setDateFormat:@"yyyy-MM-dd"];
    NSMutableSet *weeks = [[NSMutableSet alloc] init ];

    for(int i = 0; i < range.length; i++)
    {
        NSString *temp = [NSString stringWithFormat:@"%4d-%2d-   %2d",year,month,range.location+i];
        NSDate *date = [dateFormatter dateFromString:temp ];
        int week = [[cCalendar components: NSWeekOfYearCalendarUnit fromDate:date] weekOfYear];
        [weeks addObject:[NSNumber numberWithInt:week]];
    }

    return [weeks count];
}

The returned value is 6 on io6 and 5 on io5.

Do you have any idea ?

EDIT : Another thing, my device (ios5) is in French and the simulator (ios6) is in English. Maybe it can change something (like the first day of week ?) ?

Answer 1

Try this one :

NSDate *date = [NSDate date];//since you are forming date, put it here
NSCalendar *calender = [NSCalendar currentCalendar];
NSRange weekRange = [calender rangeOfUnit:NSWeekCalendarUnit inUnit:NSMonthCalendarUnit forDate:date];
NSInteger weeksCount=weekRange.length;
NSLog(@"%d",weeksCount);

---

Swift 4.0:

let date = Date()
let calendar = Calendar.current
let weekRange = calendar.range(of: .weekOfMonth, 
                               in: .month, 
                               for: date)
let weeksCount = weekRange.count ?? 0
print(weeksCount)

---

Or change your method to :

- (NSInteger)weeksOfMonth:(int)month inYear:(int)year{
    NSString *dateString=[NSString stringWithFormat:@"%4d/%d/1",year,month];

    NSDateFormatter *dfMMddyyyy=[NSDateFormatter new];
    [dfMMddyyyy setDateFormat:@"yyyy/MM/dd"];
    NSDate *date=[dfMMddyyyy dateFromString:dateString];

    NSCalendar *calender = [NSCalendar currentCalendar];
    NSRange weekRange = [calender rangeOfUnit:NSWeekCalendarUnit inUnit:NSMonthCalendarUnit forDate:date];
    NSInteger weeksCount=weekRange.length;

    return weeksCount;
}

---

EDIT:

use this in above method

 //NSCalendar *calender = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
 [calender setFirstWeekday:2]; //sunday=1, monday=2 etc