获取一周的开始和结束日期。 月份、周数和年份作为用户输入给出

Question

当用户提供月份、星期数和年份时，我的代码应该带上特定星期的日期。 例如：如果我的用户输入是月份 (String) --> "October", week (Int) --> 1, year (int) --> 2019，上面的输入应该给出类似 startDate --> 01 的响应/10/2019，结束日期 --> 07/10/2019。

如果用户给出任何一个月的最后一周，它应该带来该月的剩余天数。 星期从星期日开始计算。

我尝试的代码给出了当前月份/当前的开始日期和结束日期

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

cal.firstWeekday = 1;// set first week day to Monday
// 1: Sunday, 2: Monday, ..., 7:Saturday

NSDate *now = [NSDate date];
NSDate *startOfTheWeek;
NSDate *endOfWeek;
NSTimeInterval interval;
[cal rangeOfUnit:NSCalendarUnitWeekOfYear
       startDate:&startOfTheWeek
        interval:&interval
         forDate:now];
//startOfTheWeek holds the beginning of the week

endOfWeek = [startOfTheWeek dateByAddingTimeInterval:interval - 1];
// endOfWeek now holds the last second of the last week day

[cal rangeOfUnit:NSCalendarUnitDay
       startDate:&endOfWeek
        interval:NULL
         forDate:endOfWeek];
// endOfWeek now holds the beginning of the last week day

NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
formatter.dateStyle = NSDateFormatterShortStyle;
formatter.timeStyle = NSDateFormatterShortStyle;

NSLog(@"start: %@", [formatter stringFromDate:startOfTheWeek]);
NSLog(@"end:   %@", [formatter stringFromDate:endOfWeek]);

Answer 1

我想出了这个符合你的标准的我认为

NSInteger year = 2019;
NSInteger month = 11;
NSInteger week = 1;

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

cal.firstWeekday = 2;

NSDateComponents *comps = [NSDateComponents new];
comps.calendar = cal;
comps.year = year;
comps.month = month;
comps.weekday = cal.firstWeekday;
comps.weekdayOrdinal = week - 1;

NSDateComponents *startOfTheMonthComps = [NSDateComponents new];
startOfTheMonthComps.year = year;
startOfTheMonthComps.month = month;
NSDateComponents *endOfTheMonthComps = [NSDateComponents new];
endOfTheMonthComps.year = year;
endOfTheMonthComps.month = month + 1;

NSDate *startOfTheMonth = [cal dateFromComponents:startOfTheMonthComps];
NSDate *endOfTheMonth = [[cal dateFromComponents:endOfTheMonthComps] dateByAddingTimeInterval:-1];

NSDate *date = [comps date];
NSDate *startOfTheWeek;
NSDate *endOfWeek;
NSTimeInterval interval;
[cal rangeOfUnit:NSCalendarUnitWeekOfYear
       startDate:&startOfTheWeek
        interval:&interval
         forDate:date];

endOfWeek = [startOfTheWeek dateByAddingTimeInterval:interval];

startOfTheWeek = [startOfTheWeek dateByAddingTimeInterval:-1];


if ([startOfTheWeek compare:startOfTheMonth] == NSOrderedAscending) {
    startOfTheWeek = startOfTheMonth;
}

if ([endOfTheMonth compare:endOfWeek] == NSOrderedAscending) {
    endOfWeek = endOfTheMonth;
}
NSLog(@"start %@", startOfTheWeek);
NSLog(@"end %@", endOfWeek);

因此，对于 11 月的第一周，您将获得Fri Nov 1和Mon Nov 4 ，以及 9 月的最后一周 - 第 6 周，9 Sun Sep 29星期日和Mon Sep 30