检查两个日期是否相隔一个月

Question

我试图检查两个日期是否相隔1个月。我读过我应该使用components:fromDate:toDate:options:

中的这种方法NSCalendar

我的代码

#define FORMAT_DATE_TIME @"dd-MM-yyyy HH:mm"

NSDate *updateDate = [Utils getDateFromString:airport.updateOn withFormat:FORMAT_DATE_TIME];
NSDate *now = [NSDate date];
NSString *nowString = [Utils getStringFromDate:now withFormat:FORMAT_DATE_TIME];
now = [Utils getDateFromString:nowString withFormat:FORMAT_DATE_TIME];

NSCalendar *calendar = [[NSCalendar alloc] initWithCalendarIdentifier:NSCalendarIdentifierGregorian];
NSDateComponents *comps = [calendar components:NSCalendarUnitMonth fromDate:updateDate toDate:now options:0];

NSLog(@"%ld", (long)[comps year]);
NSLog(@"%ld", (long)[comps month]);
NSLog(@"%ld", (long)[comps day]);

这些是日志：

  

（lldb）年份：9223372036854775807

     

（lldb）月：0

     

（lldb）日：9223372036854775807

     

（lldb）po现在2017-08-23 11:54:00 +0000

     

（lldb）po updateDate 2017-08-23 11:48:00 +0000

不应该将所有值都归零吗？

Answer 1

以下行不包含年份（NSCalendarUnitYear）和日期（NSCalendarUnitDay）组件，仅包含月份（NSCalendarUnitMonth）组件。

NSDateComponents *components = [calendar components:NSCalendarUnitMonth fromDate:updateDate toDate:now options:0];

添加NSCalendarUnitYear和NSCalendarUnitDay以获得[comps year]＆amp; [comps day]为0。

像这样：

NSDateComponents * components = [calendar components:NSCalendarUnitMonth |NSCalendarUnitYear|NSCalendarUnitDay fromDate:updateDate toDate:now options:0];

Answer 2

你可以用这个

 NSDateFormatter *dateFormatter = [[NSDateFormatter alloc] init];
[dateFormatter setDateFormat:FORMAT_DATE_TIME];
NSDate *updateDate  = [dateFormatter dateFromString:@"24-07-1990 15:20"];

NSDate *now = [NSDate date];


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

unsigned unitFlags = NSCalendarUnitYear | NSCalendarUnitMonth |  NSCalendarUnitDay;


NSDateComponents *comps = [calendar components:unitFlags fromDate:updateDate toDate:now options:0];


NSLog(@"%ld", (long)[comps year]);
NSLog(@"%ld", (long)[comps month]);
NSLog(@"%ld", (long)[comps day]);