如何通過使用兩個不同的日期選擇器找到兩個日期之間的差異

Question

我做了一個代碼來使用兩個不同的日期選擇器找到兩個日期之間的差異。我無法找到兩個日期之間的差異。兩個日期的差別總是爲零。

@property (strong, nonatomic) IBOutlet UILabel *date1; 
@property (strong, nonatomic) IBOutlet UILabel *date2; 
- (IBAction)cale1:(id)sender; 
- (IBAction)cale2:(id)sender; 
@property (strong, nonatomic) IBOutlet UIDatePicker *datePicker1; 
@property (strong, nonatomic) IBOutlet UIDatePicker *datePicker2; 
@property NSDate *d1,*d2; 

@implementation ViewController 

- (IBAction)cale1:(id)sender { 
    NSDateFormatter *dc=[[NSDateFormatter alloc]init]; 
    dc.dateStyle=NSDateFormatterFullStyle; 
    _d1=_datePicker1.date; 
    _date1.text=[dc stringFromDate:_datePicker1.date]; 
    NSLog(@"Date %@",_date1); 
} 

- (IBAction)cale2:(id)sender { 
    NSDateFormatter *dc=[[NSDateFormatter alloc]init]; 
    dc.dateStyle=NSDateFormatterFullStyle; 
    _d2=_datePicker2.date; 
    _date2.text=[dc stringFromDate:_datePicker2.date]; 
    NSLog(@"Date %@",_d2); 

    [self isSameDay:_d1 otherDay:_d2]; 

} 
-(BOOL)isSameDay:(NSDate *)date1 otherDay:(NSDate *)date2{ 
    NSCalendar *cale=[NSCalendar currentCalendar]; 
    unsigned unitFlags=NSYearCalendarUnit| NSMonthCalendarUnit| NSDayCalendarUnit; 
    NSDateComponents *comp1=[cale components:unitFlags fromDate:date1]; 
    NSDateComponents *comp2=[cale components:unitFlags fromDate:date2]; 


    // NSString *comp=[NSString stringWithFormat:@"%d", [comp1 day]==[comp2 day]&&[comp1 month]==[comp2 month]&&[comp1 year]==[comp2 year]]; 
    BOOL a=[comp1 day]==[comp2 day]&&[comp1 month]==[comp2 month]&&[comp1 year]==[comp2 year]; 

    NSLog(@"Date Differ%hhd",a); 
    return a; 
} 

Answer 1

比較方法有效日期中的日期是？

如果他們是你可以這樣做：如果日期是不一樣的

BOOL difference = [date1 timeIntervalSinceDate:date2] > 0; 

差異將是真實的。 timeIntervalSinceDate返回NSTimeInterval這是：

用於指定時間間隔，以秒爲單位。

Answer 2

爲了比較兩個日期，你需要使用NSDateComponents.I修改你的函數「isSameDay」。它返回兩個日期之間的日差數。

-(int)isSameDay:(NSDate *)date1 otherDay:(NSDate *)date2 
{  
    NSDateComponents *components; 

    int days; 

    components = [[NSCalendar currentCalendar] components: NSDayCalendarUnit 
              fromDate: date1 toDate: date2 options: 0]; 
    days = (int) [components day]; 

    NSLog(@"days %d",abs(days)); 

    return days; 

}