如何在laravel中访问数组内部集合中的属性

Question

我有一个集合，其中有一个数组作为项目，我想知道如何在我的代码中访问它，这是集合的dd：

Collection {#990
  #items: array:1 [
    0 => RoomPricingHistory {#971
      #fillable: array:19 [
        0 => "accommodation_room_id"
        1 => "net_price"
        2 => "sales_price"
        3 => "extra_bed_price"
        4 => "half_charge_price"
        5 => "half_board_price"
        6 => "full_board_price"
        7 => "foreign_net_price"
        8 => "foreign_sales_price"
        9 => "foreign_extra_bed_price"
        10 => "foreign_half_charge_price"
        11 => "foreign_half_board_price"
        12 => "foreign_full_board_price"
        13 => "operator_id"
        14 => "commission_percent"
        15 => "discount_percent"
        16 => "from_date"
        17 => "to_date"
        18 => "is_deleted"
      ]
      #connection: "mysql"
      #table: "room_pricing_histories"
      #primaryKey: "id"

这是我尝试的代码：

 $sum_price[] = $room_price[$i]->sales_price;

它在for循环中，但出现此错误：

  

此集合实例上不存在属性[sales_price]。