在循环内更改全局变量

Question

import turtle    

t = turtle.Turtle()

times = int(input("How many points would you like to draw?"))


for side in range (times):

    move = input("which way would you like too go?\n\n1: Forward\n2: Backward\n3: Right\n4: Left\n5: Change Color\n6: Exit")

    if (move == str(1)):
        t.forward(50)

    if (move == str(2)):
        t.backward(50)

    if (move == str(3)):
        t.right(90)

    if (move == str(4)):
        t.left(90)

    if(move == str(5)):
        color = input("What color would you like?")
        t.color(color)

    if (move == str(6)):
        break

    else:
        break

（这可能是一个愚蠢的问题，我对python来说还很陌生）我想使用用户输入使乌龟移动，并使它移动正常，但我想更改乌龟的颜色并使颜色在内部保持不变循环。 我不确定如何执行此操作或对此进行研究，所以我在这里提出疑问。

谢谢

Answer 1

else:
    break

这else无论何时将执行if前一个是假：

if (move == str(6)):
    break

因此，只要move为6 ，您的循环就会结束。

如果只想在move不是1或2或3或4或5或6时中断， if除第一个以外的所有if更改为elif 。

if (move == str(1)):
    t.forward(50)

elif (move == str(2)):
    t.backward(50)

elif (move == str(3)):
    t.right(90)

elif (move == str(4)):
    t.left(90)

elif(move == str(5)):
    color = input("What color would you like?")
    t.color(color)

elif (move == str(6)):
    break

else:
    break

Answer 2

将除第一个以外的所有if语句更改为elif 。 问题在于else:最后仅附加到if (move == str(6)):因此除6以外的任何移动都将导致您跳出循环。

if (move == '1'):
    t.forward(50)

elif (move == '2'):
    t.backward(50)

elif (move == '3'):
    t.right(90)

elif (move == '4'):
    t.left(90)

elif(move == '5'):
    color = input("What color would you like?")
    t.color(color)

elif (move == '6'):
    break

else:
    break

另外，只需写'1'而不是str(1) 。 或将输入转换为int ，然后仅if move == 1: