关于python：为什么我的函数keymovespire()不能看到全局变量x_coordinate，y_coordinate？

Why can't my function keyMoveSprite() see the global variable x_coordinate, y_coordinate?

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感谢您的帮助。我刚接触到Python语言，并使用这个项目来学习Python，现在它使用一个函数来绘制屏幕上的瓷砖，我正在努力让sprite能够通过按键移动。问题是我的函数keymoveSpire()看不到全局变量x_坐标和y_坐标。它们在我的函数中，但这导致了sprite不移动，因为每次迭代x和y变量都被设置回0，所以我认为它们需要在循环之外。有什么建议吗？这是我的密码。我认为这个问题可能是因为在游戏的主循环中，函数被反复调用，但是需要反复调用它来跟踪输入。

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import pygame,sys
from pygame.locals import *

pygame.init()

#Global Variables
screen_x = 800
screen_y = 480
screen = pygame.display.set_mode((screen_x, screen_y))
x_coordinate = 0
y_coordinate = 0
moveX, moveY = 0, 0

#This function will take the screen coordinates and draw
#a tile to the entire screen. It will draw tiles no matter
#the screen size.

def keyMoveSprite():
sprite = pygame.image.load("character.png").convert_alpha()

for event in pygame.event.get():

if event.type == KEYDOWN:
if event.key == K_LEFT:
moveX = -10
elif event.key == K_RIGHT:
moveX = +10
elif event.key == K_UP:
moveY = -10
elif event.key == K_DOWN:
moveY = +10

if event.type == KEYUP:
if event.key == K_LEFT:
moveX = 0
elif event.key == K_RIGHT:
moveX = 0
elif event.key == K_UP:
moveY = 0
elif event.key == K_DOWN:
moveY = 0

x_coordinate = x_coordinate + moveX
y_coordinate = y_coordinate + moveY

screen.blit(sprite,(x_coordinate, y_coordinate))
pygame.display.update()
print("Character drawn at:", x_coordinate, y_coordinate)

def mapDraw(screen_x, screen_y):

floor = pygame.image.load("floor_tile.png")
wall = pygame.image.load("wall_tile.png")
treasure = pygame.image.load("treasure_chest.png")

# Intialize row for loop
row = 0
mapColumn = 0
mapRow = 0

#Loop between the values 0 to the screen's y variable, in intervals of
#32, and store them in the variable row once per loop.

mapArray = [
[1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1],
[1,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
[1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,1],
[1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1]
]

for row in range(0, screen_y, 32):
column = 0 # Set column to 0 per iteration, this allows reset of the x coordinate
print("Map Row Value:", mapRow)
mapColumn = 0 # Resets mapColumn variable to 0
for column in range(0, screen_x, 32):

if mapArray[mapRow][mapColumn] == 0:

screen.blit(floor, (column, row))
#print(column,row)
pygame.display.update()
#print("Map Column Value:",mapColumn)
print("MapCol",mapColumn,"MapRow",mapRow)

elif mapArray[mapRow][mapColumn] == 1:
screen.blit(wall, (column, row))
pygame.display.update()

mapColumn = mapColumn + 1

mapRow = mapRow + 1

def main():

mapFloor = mapDraw(800,480)
while True:

keyMoveSprite()

main()

尝试使用global关键字，这样解释器就可以在x_coordinate和y_coordinate的本地赋值之间消除歧义：

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def keyMoveSprite():
global x_coordinate, y_coordinate
# The rest of your code...

解决这个问题的一个更好的方法是创建一个类来表示你的玩家、它的位置以及与之相关的其他状态，而不是将所有内容存储在全局中。