对NSArray中自定义的对象进行排序

场景：Person类 

@interface Person : NSObject
@property (nonatomic, copy) NSString *name;
@property (nonatomic, copy) NSString *surname;
@property (nonatomic, strong) NSDate *dateOfBirth;
@end

根据类中的任意对象作为排序的对象

使用NSComparator进行排序

    NSArray *sortArray1 = [mPersonArray sortedArrayUsingComparator:^NSComparisonResult(Person *p1, Person *p2) {
        
        return [p1.surname compare:p2.surname];
    }];

使用NSDescriptor进行排序

    NSSortDescriptor *secondDescriptor = [[NSSortDescriptor alloc] initWithKey:@"name"
                                                                     ascending:YES];
    NSArray *sortDescriptors = [NSArray arrayWithObjects:secondDescriptor, nil];
    NSArray *sortArray2 = [mPersonArray sortedArrayUsingDescriptors:sortDescriptors];