Question

对于一副扑克牌：

创建包时如何使用套装哈希（下面）？

我有：

class PackOfCards

  SUITS={H: 'Hearts', S:'Spades', D:'Diamonds', C:'Clubs'}
  CARDS=['A','2','3','4','5','6','7','8','9','10','J','Q','K']


  attr_accessor :pack_name, :cards

  def initialize(pack_name)

    @pack_name= pack_name
    @cards = []
    (0..3).each do |suit|
      (0..12).each do |number|
        @cards << PlayingCard.new(self, (SUITS[suit].value), CARDS[number])
      end 
    end 
  end 
end

class PlayingCard

  attr_accessor :pack, :card_number, :card_suit


  def initialize(pack, suit, number)
    @card_suit = suit
    @card_number = number
  end 

end

但我明白了：

pack_of_cards.rb:16:in `block (2 levels) in initialize': 
undefined method `value' for 
{:H=>"Hearts", :S=>"Spades", :D=>"Diamonds", :C=>"Clubs"}:Hash (NoMethodError)

Answer 1

~~你的SUITS表达无效。~~也许你想这样做：

SUITS = %w[Hearts Spades Diamonds Clubs]

目前尚不清楚你在做什么，但也许你应该这样做：

@cards =
SUITS.flat_map{|suit| CARDS.map{|number| PlayingCard.new(self, suit, number)}}

Answer 2

以下是更正后的版本，请查看评论：

class PackOfCards
  SUITS={H: 'Hearts', S:'Spades', D:'Diamonds', C:'Clubs'} # Use curly braces to define a hash, [] braces will define an array containing one hash
  CARDS=['A','2','3','4','5','6','7','8','9','10','J','Q','K']
  attr_accessor :pack_name, :cards

  def initialize(pack_name)
    @pack_name= pack_name
    @cards = []
    SUITS.each_key do |suit| # each_key is better since it gives you the key of the hash
      (0..12).each do |number|
        puts PackOfCards::SUITS[suit]
        @cards << PlayingCard.new(self, (PackOfCards::SUITS[suit]), PackOfCards::CARDS[number]) # Call the hash with the right key to get the Suit
      end
    end
  end
end

class PlayingCard 
  attr_accessor :pack, :card_number, :card_suit

  def initialize(pack, suit, number)
    @card_suit = suit
    @card_number = number
  end

end

Answer 3

您的Suit定义和查找效果不佳。

这样的事情怎么样（假设输出是一包带有所有套装和数字的卡片） -

class PackOfCards

  SUITS = ['Hearts', 'Spades', 'Diamonds', 'Clubs']
  CARDS=['A','2','3','4','5','6','7','8','9','10','J','Q','K']


  attr_accessor :pack_name, :cards

  def initialize(pack_name)

    @pack_name= pack_name
    @cards = []
    (0..3).each do |suit|
      (0..12).each do |number|
        @cards << PlayingCard.new(self, (SUITS[suit]), CARDS[number])
      end 
    end 
  end 
end

class PlayingCard

  attr_accessor :pack, :card_number, :card_suit


  def initialize(pack, suit, number)
    @card_suit = suit
    @card_number = number
  end 

end

Answer 4

您实际上已在数组中放入哈希。要访问键，值对，您必须首先访问数组元素，如下所示：

SUITS.first[:H]

Ruby哈希 - 如何在填充对象时使用哈希值？

4 个答案: