刪除陣列嵌套一個NSArray的（目標C）

Question

我在myarray的這種模式：

myArray[0][0] = "28.04" 
myArray[1][0] = "21.12" 
myArray[2][0] = "12.33" 

，我想有這樣的：

myArray[0] = "28.04" 
myArray[1] = "21.12" 
myArray[2] = "12.33" 

Answer 1

您需要稱爲高階函數flatmap

- (NSArray *)flatMap:(id (^)(id obj))block { 
    NSMutableArray *mutableArray = [NSMutableArray new]; 
    [self enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) { 
     id _obj = block(obj); 
     if ([_obj isKindOfClass:[NSArray class]]) { 
      NSArray *_array = [_obj flatMap:block]; 
      [mutableArray addObjectsFromArray:_array]; 
      return; 
     } 
     [mutableArray addObject:_obj]; 
    }]; 
    return mutableArray; 
}