Question

如何计算仅包含周数和星期几的日期？

E.g。 2012年周二，第24周，周一开始。

Answer 1

非常方便，NSCalendar将为您完成所有数学运算。首先，使用NSDateComponents设置参数：

NSDateComponents *comps = [[NSDateComponents alloc] init];
[comps setWeek:24];
[comps setWeekday:3]; //map weekday names to numbers (e.g., Sunday is 1)
[comps setYear:2012];

然后使用这些日期组件创建公历日历：

 NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];

抓住你的NSDate：

 NSDate *date = [gregorian dateFromComponents:comps];

Answer 2

    NSDate *now = [NSDate date];
    NSCalendar *gregorian = [[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
    NSDateComponents *comp = [gregorian components:NSYearCalendarUnit fromDate:now];
    [comp setWeek:24];
    [comp setDay:1]; 
    NSDate *resultDate = [gregorian dateFromComponents:comp];
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateFormat:@"MMM d, yyyy"];


    NSString *myDateString = [formatter stringFromDate:resultDate];

    [gregorian release]; // Clean up allocated objects by releasing them
    [formatter release];

    NSString * date = [NSString stringWithFormat:@"Week of %@", myDateString];

从周数计算日期

2 个答案: