为什么我的 python if 语句不起作用？
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Why is my python if statement not working?
提问by user3311991
I hope someone can help me. when I run the below function, no matter what the input, the rules are printed. I can't see what I've done wrong.
我希望有一个人可以帮助我。当我运行下面的函数时，无论输入是什么，都会打印规则。我看不出我做错了什么。
def check_rules():
while True:
request = input("\nWould you like to know the rules? (y/n) ")
if request == "y" or "Y":
print("""
1. Each player takes it in turn to roll a dice.
2. The player then turns over a card with the same
number as the number rolled to see how many ladybirds
there are (0-3).
3. The player keeps the card.
4. If a player rolls a number that is not on an unclaimed
card, play continues to the next player.
5. Play continues until there are no more cards.
6. The player with the most number of ladybirds wins.""")
break
elif request == "n" or "N":
break
else:
print("\nI'm sorry, I didn't understand that.")
采纳答案by pseudocubic
Your if statement is not formed correctly:
您的 if 语句格式不正确：
def check_rules():
while True:
request = input("\nWould you like to know the rules? (y/n) ")
if request in ["y","Y"]:
print("""
1. Each player takes it in turn to roll a dice.
2. The player then turns over a card with the same
number as the number rolled to see how many ladybirds
there are (0-3).
3. The player keeps the card.
4. If a player rolls a number that is not on an unclaimed
card, play continues to the next player.
5. Play continues until there are no more cards.
6. The player with the most number of ladybirds wins.""")
break
elif request in ["n","N"]:
break
else:
print("\nI'm sorry, I didn't understand that.")
Boolean expressions cannot be like if something == x or y, you must state them like if something == x or something == y
布尔表达式不能像if something == x or y，你必须像if something == x or something == y
回答by HahaHortness
The ifstatement doesn't determine whether request equals yor Y. If determines the boolean value of request == "y"which may be false. If it's false it then determines the boolean value of "Y". Since a non empty string evaluates to True request == "y"or "Y"is always true.
该if语句不确定 request 是等于y还是Y。如果确定其布尔值request == "y"可能为假。如果为假，则确定 的布尔值"Y"。由于非空字符串的计算结果为 Truerequest == "y"或"Y"始终为真。
