功能之间的价值丢失？

Question

我正在开发一个简单的基于文本的战斗游戏，但遇到了一个（另一个）问题。我有一个主要功能和一个战斗功能，在战斗功能中，一旦您完成战斗，您将获得一定数量的 XP，然后（或应该）通过更改 player1.xp 的值来记住它。在战斗序列之后，我在代码中设置了它，如果 player1.xp >= 1，它会将 player1.level 的值更改为“2”。但是，每当我运行代码时，由于某种原因，战斗功能完成时 xp 值会丢失。我知道这是因为它在战斗功能后打印出 player1.xp 的值，并且显示为“0”。代码如下：

import random
xp1 = random.randint(1,2)
class player:
    def __init__ (self, name, health, strength, defense, potion, xp, level):
        self.health = health
        self.strength = strength
        self.defense = defense
        self.name = name
        self.potion = potion
        self.xp = xp
        self.level = level

    def changeHealth(self, h):
        self.health = h

    def addLevel(self):
        self.level += 1

    def subHealth(self, num):
        self.health -= num
        return self.health

    def subPotion(self):
        self.potion -= 1
        return self.health

    def addPotion(self, num1):
        self.potion += num1

    def addHealth(self):
        self.health +=2

    def addXP(self):
        self.xp += xp1

def battle1(enemy, player1, name1):
    player1 = player(name1, player1.health, player1.strength, player1.defense, player1.potion, player1.xp, player1.level)
    enemy = player("Rat", enemy.health, enemy.strength, enemy.defense, player1.potion, enemy.xp, enemy.level)
    print("Fight!")
    s = 0
    while s == 0:
        attack =input("Type 1 to attack, type 2 to use a potion.")

        if attack == "1":

            enemy.subHealth(15)

        elif attack == "2":

            if player1.potion > 0:
                print("You used a potion.")

            elif player1.potion <= 0:
                print("You don't have any potions! You are forced to attack.")
                enemy.subHealth(15)
        else:
            print("Your life depends on this!")

        if enemy.health <= 0:
            print("Congratulations, you won! You recieved", xp1, "xp!")
            player1.addXP()
            s = 2

def main():

    name1 = input("What would you like your name to be?")
    print("Hello,", name1, "you are on a quest to save otis from the evil Dongus. You must slay him, or Otis will poop.")
    player1 = player(name1, 10, 2, 1, 0, 0, 1)
    enemy = player("Rat", 15, 0, 0, 0, 0, 0)
    pick = input("You were walking along the path and found a potion! Press 'p' to pick it up.")
    if pick == "p":
        print("You added a potion to your inventory.")
        player1.addPotion = 1
    else:
        print("You have no potions, you should probably pick this one up.")
        print("You added a potion to your inventory.")
        player1.addPotion = 1
    battle1(enemy, player1, name1)
    print(player1.xp)
    if player1.xp >= 1:
        print("You leveled up. You are now level 2.")
        player1.addLevel()
    else:
        print("You have 0 xp.")

main()

有人知道为什么会这样吗？谢谢！

Answer 1

在main 中创建两个player (should be Player) 实例，并将它们传递给battle1：

player1 = player(name1, 10, 2, 1, 0, 1)
enemy = player("Rat", 15, 0, 0, 0, 0)
battle1(enemy, player1, name1)

在battle1 中创建两个新的player 实例，基于这两个参数实例，修改新实例，不要return 做任何事情：

# take three parameters (one of which is unnecessary)
def battle1(enemy, player1, name1):
    # replace two of the arguments with copies
    player1 = player(name1, player1.health, player1.strength, player1.defense, player1.xp, player1.level)
    enemy = player("Rat", enemy.health, enemy.strength, enemy.defense, enemy.xp, enemy.level)
    # original arguments now inaccessible

不清楚您为什么期望这会起作用，但最小的解决方法是停止在 battle1 中创建新实例。此外，如果您将xp1 = random.randint(1,2) 移到内部 battle1，可能会更清楚。