iPhone NSDate例如。下周五

Question

我想创建一个函数，导致下周五的日期，但我没有计划如何去做。有没有人给我一个好的提示？

Answer 1

E.g.使用NSDate获取当前日期，然后使用NSCalendar的'components> fromDate：'获取NSDateComponents，然后将时间差添加到下一个星期五，并创建一个新的NSDate，Bob's是您的叔叔。

Answer 2

这是我的解决方案，只是为了提醒你，星期六是星期五展示之前。 欢呼所有

NSDate *today = [[NSDate alloc] init]; 
NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar]; 

NSDateComponents *weekdayComponents = [gregorian components:NSWeekdayCalendarUnit fromDate:today]; 
int weekday = [weekdayComponents weekday]; 


int iOffsetToFryday = -weekday + 6; 
weekdayComponents.weekday = iOffsetToFryday; 

NSDate *nextFriday = [[NSCalendar currentCalendar] dateByAddingComponents:weekdayComponents toDate:today options:0]; 

Answer 3

这里是获取未来5日在公历我工作的解决方案：

self.nextBeginDates = [NSMutableArray array]; 

NSDateComponents *weekdayComponents = [[NSCalendar currentCalendar] components:NSWeekdayCalendarUnit fromDate:[NSDate date]]; 
int currentWeekday = [weekdayComponents weekday]; //[1;7] ... 1 is sunday, 7 is saturday in gregorian calendar 

NSDateComponents *comp = [[NSDateComponents alloc] init]; 
[comp setDay:8 - currentWeekday]; // add some days so it will become sunday 

// build weeks array 
int weeksCount = 5; 
for (int i = 0; i < weeksCount; i++) { 
    [comp setWeek:i]; // add weeks 

    [nextBeginDates addObject:[[NSCalendar currentCalendar] dateByAddingComponents:comp toDate:[NSDate date] options:0]]; 
} 
[comp release]; 

Answer 4

这应该工作

+ (NSDate *) dateForNextWeekday: (NSInteger)weekday { 

NSDate *today = [[NSDate alloc] init]; 
NSCalendar *gregorian = [[NSCalendar alloc] 
         initWithCalendarIdentifier:NSGregorianCalendar]; 

// Get the weekday component of the current date 
NSDateComponents *weekdayComponents = [gregorian components:NSWeekdayCalendarUnit 
                fromDate:today]; 

/* 
Add components to get to the weekday we want 
*/ 
NSDateComponents *componentsToSubtract = [[NSDateComponents alloc] init]; 
NSInteger dif = weekday-weekdayComponents.weekday; 
if (dif<=0) dif += 7; 
[componentsToSubtract setDay:dif]; 

NSDate *beginningOfWeek = [gregorian dateByAddingComponents:componentsToSubtract 
                toDate:today options:0]; 

return beginningOfWeek; 

}

Answer 5

保持它简单，安全，可读！ （.... KISSAR？）

#define FRIDAY 6 

NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar]; 
NSDateComponents *dayComponent = [[NSDateComponents alloc] init]; 
dayComponent.day = 1; 

NSDate *nextFriday = [NSDate date]; 
NSInteger iWeekday = [[gregorian components:NSWeekdayCalendarUnit fromDate:nextFriday] weekday]; 

while (iWeekday != FRIDAY) { 
    nextFriday = [gregorian dateByAddingComponents:dayComponent toDate:nextFriday options:0]; 
    iWeekday = [[gregorian components:NSWeekdayCalendarUnit fromDate:nextFriday] weekday]; 
} 

现在nextFriday有你的约会。

希望这会有所帮助！

编辑 请注意，如果当前日期已经是星期五，它将返回，而不是下一个星期五。如果这是不可取的，只需在一天之后启动nextFriday（所以如果当前日期是星期五，它将在星期六开始，迫使下一个星期五。如果当前日期是星期四，您将自动在下个星期五不需要循环）。