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  • iOS开发之数组排序

    1、数组按照指定关键字升序

    NSArray *sortedArray = [unSortedArray sortedArrayUsingComparator:^(id obj1,id obj2)
    {
      //升序,key表示比较的关键字
       if (obj1.key < obj1.key )
      {
         return NSOrderedAscending;
      }
      else
      {
         return NSOrderedDescending;
      }
    }

    2、数组按照指定关键字降序

    NSArray *sortedArray = [unSortedArray sortedArrayUsingComparator:^(id obj1,id obj2)
    {
      //降序,key表示比较的关键字
       if (obj1.key < obj1.key )
      {
         return NSOrderedDescending;
      }
      else
      {
         retur NSOrderedAscending;
      }
    }

    3、数组顺序全部翻转

    NSMutableArray *tempArray = [NSMutableArray arrayWithObjects:@"1",@"2",@"3",@"4",@"5",@"6",nil];
    NSArray *resultArray = [[tempArray reverseObjectEnumerator] allObjects];

    4、使用NSDescriptor排序

    单个关键字排序

    NSMutableArray *array = [NSMutableArray array];    
    NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"key" ascending:YES];
    [array sortUsingDescriptors:[NSArray arrayWithObject:sort]]; 

    多个关键字排序

    NSMutableArray *array = [NSMutableArray array];  
    NSSortDescriptor *sort1 = [NSSortDescriptor sortDescriptorWithKey:@"key1" ascending:YES];  
    NSSortDescriptor *sort2 = [NSSortDescriptor sortDescriptorWithKey:@"key2" ascending:NO]; 
    ......   
    [array sortUsingDescriptors:[NSArray arrayWithObjects:sort1, sort2, nil]];
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  • 原文地址:https://www.cnblogs.com/hecanlin/p/10898676.html
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