我的 else 语句不起作用。怎么了？ [复制]答案

【问题标题】：My else statement doesn't work. What is wrong? [duplicate]我的 else 语句不起作用。怎么了？ [复制]
【发布时间】：2022-11-18 16:08:42
【问题描述】：

所以在 if 语句中，如果玩家没有输入正确的内容，我想打印一条消息。问题是当我启动代码并随机输入一些东西时，如果它检查是并继续前进，它会跳到第一个。它甚至为我回复了下一个功能。有没有办法来解决这个问题？

import time

yes_no = ['yes', 'y', 'no', 'n']
directions = ['north', 'n', 'south', 's', 'east', 'e', 'west', 'w']
else_msg = "Invalid command"


def start():
    print("-------------------------------")
    print("Welcome to Haunted Funhouse")
    print("Do you want to proceed? (y/n)")
    cmd = input(">")
    if cmd in yes_no:
        if cmd == "yes" or "y":
            time.sleep(1)
            print("\n------------------")
            print("Get ready")
            print("--------------------\n")
            starting_room()
        elif cmd == "no" or "n":
            time.sleep(1)
            print("Okay, shutting down")
            quit()
        else:
            print(else_msg)


def starting_room():
    print("-----------Start-----------")
    print("You stand in a octagon room")
    print(
        "There are windows to the northwest, northeast, southeast, southwest")
    print("There are doors to the:\n- North\n- South\n- East\n- West")
    print("---------------------------------------------------------")
    print("Where do you want to go? (n/s/e/w)")
    cmd = input(">")
    if cmd in directions:
        if cmd == "north" or "n":
            time.sleep(1)
            print("You enter through the north door")
        elif cmd == "south" or "s":
            time.sleep(1)
            print("You go through the south door")
        elif cmd == "west" or "w":
            time.sleep(1)
            print("You enter through the west door")
        elif cmd == "east" or "e":
            time.sleep(1)
            print("You enter through the east door")
        else:
            print(else_msg)


start()

我试过将“如果 cmd 不在 yes_no”中更改为“如果 cmd 在 yes_no 中”，但它没有用。我通过 Thonny 运行它，代码检查器说没问题

【问题讨论】：

标签： python

【解决方案1】：

更改如下：

if cmd in yes_no:
    if cmd == "yes" or cmd == "y":
        time.sleep(1)
        print("
------------------")
        print("Get ready")
        print("--------------------
")
        starting_room()
    elif cmd == "no" or cmd == "n":
        time.sleep(1)
        print("Okay, shutting down")
        quit()

【讨论】：

【解决方案2】：

你需要改变：

if cmd == "yes" or "y"

至

if cmd == "yes" or cmd == "y"

..在代码的其他部分也类似。

如果 cmd == 'no' 则此测试将为真，因为非空字符串为真。

另一种构造可能是：

if cmd in {'yes', 'y'}

【讨论】：