如果我不知道要添加多少变量，如何向类添加更多变量 (python)

Question

I'm just making a blackjack game on python. So I have a player class and I set player's variables as the cards the user gets. So you start with 2 cards. But as the user wants to get more cards I have to add new cards to the class. How would I do that? It seems redundant to make a bunch of unassigned variables and assign them as the user gets more cards.

class Player:
    def __init__(self, pcard1, pcard2):
        self.Pcard1 = pcard1
        self.Pcard2 = pcard2

    def player_starting_cards(self):
        print("Your cards are " + str(self.Pcard1) + " and " + str(self.Pcard2))

Answer 1

Your best bet would be to have a list of cards and append to it. Something like:

class Player:
    def __init__(self, *cards):
        self.cards = cards

    def player_starting_cards(self):
        print("Your cards are " + " and ".join(self.cards))

The proper way to add fields to an object, however is with setattr :

>>> class A():
...     pass
...
>>> a = A()
>>> a.__dict__ # Contain object attributes
{}
>>> setattr(a, "my_attr", 42)
>>> a.__dict__
{'my_attr': 42}

Hope that helps.

Answer 2

Use some sort of collection type like a list of dict. These are single things that can hold multiple things.

EG:

class Player:
    def __init__(self, cards):
        self.card_list = cards

    def player_starting_cards(self):
        print("Your cards are {}".format(', '.join(self.card_list)))

player = Player(['qh', '3c'])
player.player_starting_cards()

You may finding yourself wanting a Card class that knows how to order cards from highest value to lowest, or able to collect cards by suit or numerically (3 deuces, or all hearts, for EG).

Answer 3

您可以使用列表来实现所需的目标，而不是为您可能拥有的每个值分配一个属性