iOS 获取一周的每一天

最近做项目遇到要获取当前时间所在一周的时间，通过网上查阅资料解决了，在这里记录一下。

/**
 *  获取当前时间所在一周的第一天和最后一天
 */
- (void)getCurrentWeek
{
    NSDate *now = [NSDate date];
    NSCalendar *calendar = [NSCalendar currentCalendar];
    NSDateComponents *comp = [calendar components:NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay|NSCalendarUnitWeekday
                                         fromDate:now];
    // 得到星期几
    // 1(星期天) 2(星期二) 3(星期三) 4(星期四) 5(星期五) 6(星期六) 7(星期天)
    NSInteger weekDay = [comp weekday];
    // 得到几号
    NSInteger day = [comp day];

    NSLog(@"weekDay:%ld  day:%ld",weekDay,day);

    // 计算当前日期和这周的星期一和星期天差的天数
    long firstDiff,lastDiff;
    if (weekDay == 1) {
        firstDiff = 1;
        lastDiff = 0;
    }else{
        firstDiff = [calendar firstWeekday] - weekDay;
        lastDiff = 7 - weekDay;
    }

    NSArray *currentWeeks = [self getCurrentWeeksWithFirstDiff:firstDiff lastDiff:lastDiff];

    NSLog(@"firstDiff:%ld   lastDiff:%ld",firstDiff,lastDiff);

    // 在当前日期(去掉了时分秒)基础上加上差的天数
    NSDateComponents *firstDayComp = [calendar components:NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay fromDate:now];
    [firstDayComp setDay:day + firstDiff];
    NSDate *firstDayOfWeek= [calendar dateFromComponents:firstDayComp];

    NSDateComponents *lastDayComp = [calendar components:NSCalendarUnitYear|NSCalendarUnitMonth|NSCalendarUnitDay fromDate:now];
    [lastDayComp setDay:day + lastDiff];
    NSDate *lastDayOfWeek= [calendar dateFromComponents:lastDayComp];

    NSDateFormatter *formater = [[NSDateFormatter alloc] init];
    [formater setDateFormat:@"yyyy-MM-dd"];
    NSLog(@"一周开始 %@",[formater stringFromDate:firstDayOfWeek]);
    NSLog(@"当前 %@",[formater stringFromDate:now]);
    NSLog(@"一周结束 %@",[formater stringFromDate:lastDayOfWeek]);

    NSLog(@"%@",currentWeeks);
}

//获取一周时间 数组
- (NSMutableArray *)getCurrentWeeksWithFirstDiff:(NSInteger)first lastDiff:(NSInteger)last{
    NSMutableArray *eightArr = [[NSMutableArray alloc] init];
    for (NSInteger i = first; i < last + 1; i ++) {
        //从现在开始的24小时
        NSTimeInterval secondsPerDay = i * 24*60*60;
        NSDate *curDate = [NSDate dateWithTimeIntervalSinceNow:secondsPerDay];                NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];         [dateFormatter setDateFormat:@"M月d日"];
        NSString *dateStr = [dateFormatter stringFromDate:curDate];//几月几号
//        NSString *dateStr = @"5月31日";
        NSDateFormatter *weekFormatter = [[NSDateFormatter alloc] init];
        [weekFormatter setDateFormat:@"EEEE"];//星期几 @"HH:mm 'on' EEEE MMMM d"];
        NSString *weekStr = [weekFormatter stringFromDate:curDate];
        //组合时间
        NSString *strTime = [NSString stringWithFormat:@"%@(%@)",dateStr,weekStr];          [eightArr addObject:strTime];
    }
    return eightArr;
}

打印结果：

weekDay:5 day:26
firstDiff:-4 lastDiff:2
一周开始 2016-05-22
当前 2016-05-26
一周结束 2016-05-28
[
2016年05日22–星期日,
2016年05日23–星期一,
2016年05日24–星期二,
2016年05日25–星期三,
2016年05日26–星期四,
2016年05日27–星期五,
2016年05日28–星期六
]