数组元素的比对

NSArray * array = [AyObjects sortedArrayUsingComparator:^NSComparisonResult(id  _Nonnull obj1, id  _Nonnull obj2) {
          if ([obj1 compare: obj2 options:NSWidthInsensitiveSearch] == NSOrderedDescending) {
                return NSOrderedAscending;
            }
            else
            {
                return NSOrderedDescending;
            }
}];

[AyObjects removeAllObjects];
[AyObjects addObjectsFromArray:array];  //拿到比对后的元素