如何使用 Pickle 加载 class 实例（初学者回到 pickle jar）

Question

我一直在浏览以前的 SO 答案，但尚未找到答案。我正在尝试使用 pickle 保存和加载 class 实例，但我不断收到错误消息：类型对象 'Foo' 没有属性 'bar'。我的代码如下：

class Char:
    name = "undefined"

    def __init__(self, race, str, int, dex, con, spd, mp_bonus):
        self.race = race
        self.exp = 0
        self.lvl = 1
        self.str = str
        self.int = int
        self.dex = dex
        self.con = con
        self.spd = spd
        self.hp = (con + str) / 2
        self.current_hp = self.hp
        self.mp_bonus = mp_bonus
        self.mp = (int * mp_bonus)
        self.current_mp = self.mp

    def save(self):
        with open("save.pk1", "wb") as fp:
            pickle.dump(self.__dict__, fp, protocol=pickle.HIGHEST_PROTOCOL)

def load():
    with open('save.pk1', 'rb') as fp:
        Char.__init__ = pickle.load(fp) # no idea what to put here 
                                        # or if it should be in the Char class or not

def options(dude):
    cls()
    print("OPTIONS")
    print("_____________________")
    print("s. Save Game")
    print("l. Load Game")
    print("x. Quit Game")
    print("_____________________")
    select = input("please type in the corresponding letter or number: ")

    if select == "s":
        Char.save(player)
        cls()
        print("Save Complete")
        wait()
        main(dude)
    elif select == "l":
        cls()
        print("Load Complete")
        wait()
        main(dude)
    elif select == "x":
        exit_screen(dude)
    else:
        print("you chose the wrong key")
        wait()
        main(dude)

  def main(dude):
      #menu as written in options above
      select = input("please type in the corresponding letter or number: ")

      if select == "s":
           stats(dude)
      elif select == "i":
           inventory(dude)
      elif select == "1":
           rand_enemy()
      elif select == "o":
           options(dude)
      else:
           print("you chose the wrong key")
           wait()
           main(dude)

   def start_screen(char):
       #menu as written in options above

       select = input("Please type in the corresponding number: ")

       if select == "1":
           get_char(char)
       elif select == "2":
           load()
           main(char)
       elif select == "3":
           exit()
       else:
           print("you chose the wrong key")
           wait()
           start_screen(char)

start_screen(Char)

所以我的主要问题是当我尝试加载游戏时，它告诉我： AttributeError: 类型对象 'Char' 没有属性 'lvl'

虽然我无法理解 pk1 文件，但它会随着每次保存而更新，所以我知道保存功能正常工作。我只是不确定如何获取 pk1 文件中的信息并替换它使用 Char.init

我正在考虑切换到 JSON，因为我已经在我的代码的其他部分实现了它。但是我想在这种情况下使用 pickle 让我的生活更轻松

Answer 1

你倾销 self.dict 的方法对我来说有点令人费解。转储 class 字符实例的常用方法如下：

class Char:
    def save(self):
        with open("save.pk1", "wb") as fp:
            pickle.dump(self, fp, protocol=pickle.HIGHEST_PROTOCOL)

def load():
    """returns the saved instance of Char"""
    with open('save.pk1', 'rb') as fp:
        return pickle.load(fp)

为了清楚起见，我把上面class的用法和方法加上去

$ python -i 53796917.py
>>> c=Char()
>>> c.lvl = 10
>>> c.save()
>>>
$ python -i 53796917.py
>>> c=load()
>>> c.lvl
10

不抛出任何 AttributeError

如何使用 Pickle 加载 class 实例（初学者回到 pickle jar）

How to load a class instance with Pickle (beginner backed into a pickle jar)

python

pickle

python-3.x