创建与NSString匹配的下一个NSDate

Question

我想创建一个NSDate对象，表示第二天与NSString日匹配。

例如。 NSString是MON或星期一我想获得与今天相匹配的下一个NSDate - 今天也是如此。

例如：NSString day = @“Tues”;

结果= 8月30日

Answer 1

NSInteger desiredWeekday = 3; // Tuesday

NSRange weekDateRange = [[NSCalendar currentCalendar] maximumRangeOfUnit:NSWeekdayCalendarUnit];
NSInteger daysInWeek = weekDateRange.length - weekDateRange.location + 1;;

NSDateComponents *dateComponents = [[NSCalendar currentCalendar] components:NSWeekdayCalendarUnit fromDate:[NSDate date]];

NSInteger currentWeekday = dateComponents.weekday;
NSInteger differenceDays = (desiredWeekday - currentWeekday + daysInWeek) % daysInWeek;

NSDateComponents *daysComponents = [[NSDateComponents alloc] init];
daysComponents.day = differenceDays;

NSDate *newDate = [[NSCalendar currentCalendar] dateByAddingComponents:daysComponents toDate:[NSDate date] options:0];

NSLog(@"newDate: %@", newDate);

2011-08-30 18:42:09.443测试[63789：707] newDate：2011-09-05 22:42:09 +0000