Compare two strings like date

Question

Need to compare two variables of type NSDate. One is the current date and the other is user selected date.

The user selects the date :

UIDatePicker *datePicker;   // declared in h file

-(void)dateChange:(id)sender{
NSDateFormatter *df = [[NSDateFormatter alloc] init];
[df setDateFormat:@"dd-MM-yyy"];
dateLabel.text = [NSString stringWithFormat:@"%@", [df stringFromDate:datePicker.date]];

userDebtInfo.duration = dateLabel.text;}

Validation Method :

-(IBAction) validation:(id)sender{
NSDate *today = [NSDate date];

NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
NSString *dateString = [dateFormat stringFromDate:today];

[dateFormat release];

 if ((userDebtInfo.debt_code == userTmp.debt_code) && ([userDebtInfo.duration compare:dateString]== NSOrderedDescending)))
            [bl updateUserMoneyValidation:userDebtInfo];  
 else
      [bl saveUserMoneyValidation:userDebtInfo];}

I have tested and is comparing two strings. Can someone help me with some advice about this condition, please? I want to compare if the selected date is after the current date to do insert or update the database.

Thank you!

Why do people always write `[NSString stringWithFormat:@"%@", otherString]`, `[NSString stringWithString:otherString]` and similar **superfluous, processortime-wasting** calls? — , Oct 02 '12 at 14:59
@H2CO3 good call, man. I just found out I have a couple of these myself xD — Cashew, Oct 02 '12 at 15:09

KarenAnne · Answer 1 · 2012-10-03T04:00:07.693

2

You could use NSDate compare function

if([firstDate compare:secondUpdate] == NSOrderedAscending){
       //This will return YES if secondUpdate is the recent date between the two dates
}

NSOrderedAscending is a constant of NSComparisonResult Here are the other constants you could compare to:

enum {
 NSOrderedAscending = -1,
 NSOrderedSame,
 NSOrderedDescending
};
typedef NSInteger NSComparisonResult;

edited Oct 03 '12 at 04:00

answered Oct 03 '12 at 03:50

KarenAnne

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g_fred · Accepted Answer · 2012-10-03T12:15:37.467

1

If you already have two objects of type NSDate, you could use one of the NSDate comparison methods. For instance [NSDate compare:] which returns a NSComparisonResult (this is the same enum as returned by [NSString compare:]).

edited Oct 03 '12 at 12:15

answered Oct 02 '12 at 15:07

g_fred

5,878
3
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Compare two strings like date

2 Answers2