iOS：获取本周的所有日期

Question

I am trying to get all dates in the current week of a given date:

In the example below, the input is

2015-11-29 23:40:37 +0000

, so I would expect the output to be an array of dates from November 23 - November 29, but the actual output is November 30 - December 6.

-(NSArray *)datesForWeekOf : (NSDate *) date {
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDate *startOfWeek;
    NSDate *endOfWeek;
    NSTimeInterval interval;

    [calendar rangeOfUnit:NSCalendarUnitWeekOfMonth startDate:&startOfWeek interval:&interval forDate:date];
    endOfWeek = [startOfWeek dateByAddingTimeInterval:interval-1];

    NSCalendar *gregorianCalendar = [[NSCalendar alloc] initWithCalendarIdentifier: NSCalendarIdentifierGregorian];

    NSDateComponents *days = [[NSDateComponents alloc] init];
    NSInteger dayCount = 0;
    NSMutableArray *allDates = [NSMutableArray array];

    while ( TRUE ) {
        [days setDay: ++dayCount];
        NSDate *date = [gregorianCalendar dateByAddingComponents: days toDate: startOfWeek options: 0];
        [allDates addObject:date];
        if ( [date compare: endOfWeek] == NSOrderedDescending )
            break;

    }
    return allDates;

}

Answer 1

You can get all dates of this week and next week using following code:-

NSArray * allDatesOfThisWeek = [self daysThisWeek];
NSArray * allDatesOfNextWeek = [self daysNextWeek];

Following methods are used for calculating dates of this week:-

-(NSArray*)daysThisWeek
{
     return  [self daysInWeek:0 fromDate:[NSDate date]];
}

-(NSArray*)daysNextWeek
{
    return  [self daysInWeek:1 fromDate:[NSDate date]];
}
-(NSArray*)daysInWeek:(int)weekOffset fromDate:(NSDate*)date
{
    NSCalendar *calendar = [NSCalendar currentCalendar];

    //ask for current week
    NSDateComponents *comps = [[NSDateComponents alloc] init];
    comps=[calendar components:NSWeekCalendarUnit|NSYearCalendarUnit fromDate:date];
    //create date on week start
    NSDate* weekstart=[calendar dateFromComponents:comps];

    NSDateComponents* moveWeeks=[[NSDateComponents alloc] init];
    moveWeeks.weekOfYear=weekOffset;            
    weekstart=[calendar dateByAddingComponents:moveWeeks toDate:weekstart options:0];


    //add 7 days
    NSMutableArray* week=[NSMutableArray arrayWithCapacity:7];
    for (int i=1; i<=7; i++) {
        NSDateComponents *compsToAdd = [[NSDateComponents alloc] init];
        compsToAdd.day=i;
        NSDate *nextDate = [calendar dateByAddingComponents:compsToAdd toDate:weekstart options:0];
        [week addObject:nextDate];

    }
    return [NSArray arrayWithArray:week];
}

If you want to get dates of next to next week from today, then pass weekOffset=2 like this:-

NSArray * allDatesOfNextToNextWeek = [self daysInWeek:2 fromDate:now];

If you want to get dates of previous week from today, then pass weekOffset=-1 like this:-

NSArray * allDatesOfPreviousWeek = [self daysInWeek:-1 fromDate:now];

Hope, this is what you're looking for. Any concern get back to me.