遍历列表检查用户的输入是否在lis中

Question

我有个问题！我试着迭代一个列表，检查一个值是否在里面，如果在里面，继续下一步，如果不在，重复输入直到用户在列表中输入一个元素

下一步，我会把我的代码，请，一些清单是做其他用途！我用的是可以吃的

DictFood = {"pasta":["spaghetti"], "meat":["beef of deer", "sasuage"], "vegetables":["chips", "letucce"], "condiment":["sugar", "salt"], "fruit":["apple", "orange"], "sweet":["chocolate"], "drink":["beer", "water"]}
TypeFood = ["pasta", "fruit", "meat", "vegetables", "condiment", "sweet", "drink"]
DictValue = {"orange":1, "spaghetti":12, "salt":0.2, "chocolate":2, "beef of deer":1, "beer":0.3, "water":0.5, "fish":3, "chips":2, "sugar":0.2, "bread":2, "apple":1, "letucce":1, "sasuage":3}
FoodAvaiable = ["orange", "spaghetti", "salt", "chocolate", "beef of deer", "beer", "water", "fish", "chips", "sugar", "bread", "apple", "letucce", "sasuage"]
x = True

def food_type():
    global user_option_f
    print("What do you want to buy?")
    print(FoodAvaiable)
    user_option_f = input()
    while x == True:
        if user_option_f == FoodAvaiable[0]: #here I have my doubt!! I've tried using "or" to add "FoodAvaibale[1]" and so on, and I got a infinite loop, I've tried "range(len(FoodAvaiable))" didn't worked too
            x == False
            print("You choose {}!".format(user_option_f))
        elif user_option_f != FoodAvaiable:
            print("You choose an element which is not avaiable! Please select one of the list")
            print(FoodAvaiable)
            print("Choose one avaiable")
            input()
    return user_option_f

food_type()

如何让我的用户输入遍历列表中的元素，检查它是否在列表中

抱歉，如果之前有人问过这个问题，我已经搜索了很多，但没有找到任何对我有帮助的东西。事先谢谢

Answer 1

您可以使用嵌套for循环来实现这一点，但正确的方法是只使用'in'操作符

while True:
    user_input = input('Food: ')
    if user_input in FoodAvailable:
        return user_input
    else:
        print('Choose one of {}'.format(', '.join(FoodAvailable)))

Answer 2

我设法在一些答案的帮助下修复了代码（感谢@UnoriginalNick和@stephernauch）

DictFood = {"pasta":["spaghetti"], "meat":["beef of deer", "sasuage"], "vegetables":["chips", "letucce"], "condiment":["sugar", "salt"], "fruit":["apple", "orange"], "sweet":["chocolate"], "drink":["beer", "water"]}
TypeFood = ["pasta", "fruit", "meat", "vegetables", "condiment", "sweet", "drink"]
DictValue = {"orange":1, "spaghetti":12, "salt":0.2, "chocolate":2, "beef of deer":1, "beer":0.3, "water":0.5, "fish":3, "chips":2, "sugar":0.2, "bread":2, "apple":1, "letucce":1, "sasuage":3}
FoodAvaiable = ["orange", "spaghetti", "salt", "chocolate", "beef of deer", "beer", "water", "fish", "chips", "sugar", "bread", "apple", "letucce", "sasuage"]


def food_type():
    x = True
    global user_option_f
    print("What do you want to buy?")
    print(FoodAvaiable)
    while x == True:
        user_option_f = input()
        if user_option_f in FoodAvaiable:
            x = False
            print("You choose {}!".format(user_option_f))
        elif user_option_f not in FoodAvaiable:
            print("You choose an element which is not avaiable! Please select one of the list")
            print(FoodAvaiable)
            print("Choose one avaiable")
            input()
    return user_option_f

food_type()

在定义之外获取输入给了我一个错误，因此我最终将其写入def并对elif进行了一些调整，也许我应该改用else，但是由于这种方式看起来很稳定，所以我将保留它