Question

对此查询的基本性质表示歉意 - 这几乎是我的第一个Python脚本。

我希望用户输入对应于扑克牌的两个字符串（例如2c，3s），并让程序检查两件事：第一，是否在有效卡列表中，第二，是否是该卡已进入。如果任一条件失败，我希望提示用户重新输入卡。我所写的内容完成了这些内容，但它并没有同时执行 - 例如，如果卡无效，则会提示用户，但如果重新输入的卡已经在列表中，则不会出现提示。我无法看到如何同时测试这两件事。

无论如何，这就是我所拥有的：

posscards=["ac",
           "2c",
           "3c",
           "4c",
           "5c" #and so on] 


for x in range(0, decksize):
        answer=raw_input("next card? ")
        while answer not in posscards:
            answer = raw_input("not a possible card - try again: ")
        while answer in deck1:
            answer = raw_input ("you've already had that one - try again: ")
        deck1.append(answer)

Answer 1

您可以使用具有两个while条件的单个while循环，而不是两个if循环。例如：

prompt = "next card? "
while True:
    answer = raw_input(prompt)
    if answer not in posscards:
        prompt = "not a possible card - try again: "
    elif answer in deck1:
        prompt = "you've already had that one - try again: "
    else:
        deck1.append(answer)
        break

如果你把它分解成一个函数，它可能会更具可读性：

def get_card():
    while True:
        answer = raw_input(prompt)
        if answer not in posscards:
            prompt = "not a possible card - try again: "
        elif answer in deck1:
            prompt = "you've already had that one - try again: "
        else:
            return answer

现在，每次拨打get_card时，都会保证（最终）回复。所以，你的主循环可能如下所示：

deck1 = []
for x in range(decksize):
    answer = get_card()
    deck1.append(answer)

你可以把它变成一个单行：

deck1 = [get_card() for x in range(deck size)]

Answer 2

顺便说一下，我没有'在任何地方看到dekk1'。确保在尝试向其附加内容之前声明。

deck1 = []

while answer not in posscards and answer in deck1:
     answer = raw_input("not a possible card or card already entered- try again: ")

Python - 检查两个同时条件的raw_input字符串？

2 个答案: