Python变量不能按预期工作

Question

我在顶部设置了3点伤害，但是当我在底部键入损伤+ = 3时它说没有引用损伤，为什么会发生这种情况？

import random, time 


inventory = ['dagger','torch'] 
hp = 50 
maxhp = 50 
damage = 3 
ac = 4 
gold = 10 
in_combat = False 

def choice(): 
    choose = input(">> ") 
    if choose == "stats": 
     print("Health:",hp,", Damage:",damage,", Armour: ",ac,", Gold:",gold) 
elif choose == "backpack": 
    print(inventory) 
elif choose == "help": 
    print("Keywords:\nstats | view your stats\nbackpack | view your inventory\nhelp | view keywords to input\nattack | attack an enemy when in combat") 
else: 
    print("Invalid Input") 




class Enemy: 
    def __init__(self, name, attack, armour, health): 
     self.name = name 
     self.attack = attack 
     self.armour = armour 
     self.health = health 

    def attack_enemy(self): 
     time.sleep(1) 
     print("What action do you want to make?\nType 'help' for a list of actions\n") 
     answer = input(">> ") 
     if answer == "attack": 
      self.health = self.health - damage 
      print(self.name,"health is: ",self.health) 



def main(): 
    while hp > 0: 
     if 'dagger' in inventory: 
      damage += 3 
     print(damage) 
     choice() 

main() 

另外，如果我改变代码的底部，将打印6匕首= 6，但是当我键入统计，它会说伤害= 3

Answer 1

可以阅读全局变量，但如果你希望为他们分配（重新绑定），你需要告诉Python你的意思是使用global关键字。

在这种情况下，根本没有必要将这些变量设置为全局变量。

您应该将这些属性移动到类中。在这个例子中，我把它叫做Player

import random, time 


class Player: 
    def __init__(self): 
     self.inventory = ['dagger','torch'] 
     self.hp = 50 
     self.maxhp = 50 
     self.damage = 3 
     self.ac = 4 
     self.gold = 10 
     self.in_combat = False 

    def choice(self): 
     choose = input(">> ") 
     if choose == "stats": 
      print("Health:", self.hp, ", Damage:", self.damage, 
        ", Armour:", self.ac, ", Gold:", self.gold) 
     elif choose == "backpack": 
      print(inventory) 
     elif choose == "help": 
      print("Keywords:\nstats | view your stats\nbackpack | view your inventory\nhelp | view keywords to input\nattack | attack an enemy when in combat") 
     else: 
      print("Invalid Input") 




class Enemy: 
    def __init__(self, name, attack, armour, health): 
     self.name = name 
     self.attack = attack 
     self.armour = armour 
     self.health = health 

    def attack_enemy(self): 
     time.sleep(1) 
     print("What action do you want to make?\nType 'help' for a list of actions\n") 
     answer = input(">> ") 
     if answer == "attack": 
      self.health = self.health - damage 
      print(self.name,"health is: ",self.health) 



def main(): 
    pl = Player() 
    while pl.hp > 0: 
     if 'dagger' in pl.inventory: 
      pl.damage += 3 
     print(pl.damage) 
     pl.choice() 

main() 

旁白：因为你很可能会被打印大量多块，抬头看dedent功能textwrap。你可以使用它是这样的：

from textwrap import dedent 

def deprint(s): 
    print(dedent(s)) 

... 


     elif choose == "help": 
      deprint(""" 
       Keywords: 
       stats | view your stats 
       backpack | view your inventory 
       help | view keywords to input 
       attack | attack an enemy when in combat""")