这里我在代码的第68行遇到问题,我在其中评估代码字符串“ snake_y = snake_y-14”如何评估赋值字符串,因为我没有看到关于eval()函数中使用的赋值操作的任何问题
import pygame
import random
import time
import sys
def basic_defaults():
pygame.init()
snake_x = 200
snake_y = 175
font_for_game_title = pygame.font.Font(None, 36)
screen = pygame.display.set_mode((800, 600)) #Making Screen for the game
screen.blit(font_for_game_title.render("Snake Game", True, (0, 255, 255)), (300, 10))# Making title appear
Clock = pygame.time.Clock()
yolo=""
return screen, snake_x, snake_y,Clock,yolo
def snake_movements():
for event in pygame.event.get():
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_UP:
yolo = "snake_y = snake_y - 14"
return yolo
elif event.key == pygame.K_DOWN:
yolo = "snake_y = snake_y + 14"
return yolo
elif event.key == pygame.K_LEFT:
yolo = "snake_x = snake_x - 14"
return yolo
elif event.key == pygame.K_RIGHT:
yolo = "snake_x = snake_x + 14"
return yolo
else:
#yolo = "snake_x += 14"
#return yolo
pass
def game_loop():
screen, snake_x, snake_y,clocko,yolo = basic_defaults()
running = True
while (running):
#for moving of snake in the game [code starts]
screen.fill((0, 0, 0))
'''for event in pygame.event.get():
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_UP:
yolo="snake_y - 14"
return yolo
elif event.key == pygame.K_DOWN:
yolo="snake_y + 14"
return yolo
elif event.key == pygame.K_LEFT:
yolo="snake_x - 14"
return yolo
elif event.key == pygame.K_RIGHT:
yolo="snake_x + 14"
return yolo
else:
pass
'''
yolo=snake_movements()
if yolo == None:
pass
else:
#print(type(yolo))
print(yolo)
eval(yolo)
#exec(yolo)
print(snake_x, snake_y)
pygame.draw.rect(screen, (102, 255, 51), (snake_x, snake_y, 10, 10), 4)
pygame.display.update()
#for moving of snake in the game [code ends]
time.sleep(1)
clocko.tick(30)
game_loop()
请快速提供帮助,因为我需要处理代码并需要完成此任务在此先感谢
对于一个人,我真的不明白为什么需要评估一个字符串,而不是直接执行该代码。最好不要使用eval()
,而只需使用代码即可。
但是,您需要的是exec()
功能。它类似于eval()
,但允许分配/定义。进一步了解exec()
与eval()
here.