IOS sorts dates

IOS sorts dates

 

NSMutableArray *array = [[NSMutableArray alloc] initWithObjects:@"2019/03/01/",@"2013/03/02",@"2013/03/07",@"2014/03/01/", [NSNull null], nil];        array = (NSMutableArray *)[array sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {        NSDateFormatter *formatter = [[NSDateFormatter alloc] init];        [formatter setDateFormat:@"yyyy/MM/dd/"];        if (obj1 == [NSNull null]) {            obj1 = @"0000/00/00";        }        if (obj2 == [NSNull null]) {            obj2 = @"0000/00/00";        }        NSDate *date1 = [formatter dateFromString:obj1];        NSDate *date2 = [formatter dateFromString:obj2];        NSComparisonResult result = [date1 compare:date2];        return result == NSOrderedAscending;    }];    for (int i = 0; i < [array count]; i++) {        NSLog(@"%@", [array objectAtIndex:i]);    }

Data needs to be sorted in the project. Here we simulate an array. because the value of the json key returned in the project is null, We need to judge whether obj1 and obj2 are empty during sorting, there are also reasons for ascending and descending order

 

 

Return result = NSOrderedAscending; ascending

 

 

Return result = NSOrderedDescending; in descending order

Ascending result:

 

 

2015-06-16 17:16:14.930 TestH5[15888:669365] 2019/03/01/2015-06-16 17:16:14.930 TestH5[15888:669365] 2014/03/01/2015-06-16 17:16:14.931 TestH5[15888:669365] 2013/03/072015-06-16 17:16:14.931 TestH5[15888:669365] 2013/03/022015-06-16 17:16:14.931 TestH5[15888:669365] 
 

Descending result:

 

 

2015-06-16 17:17:21.692 TestH5[15946:671080] 2013/03/022015-06-16 17:17:21.692 TestH5[15946:671080] 2013/03/072015-06-16 17:17:21.692 TestH5[15946:671080] 2014/03/01/2015-06-16 17:17:21.692 TestH5[15946:671080] 2019/03/01/2015-06-16 17:17:21.692 TestH5[15946:671080]