用Python第2版自动化无聊的东西-三明治制造者实践项目

Question

我正在学习过程中，虽然这是一个非常容易的项目，我仍然希望专家们能回顾它并分享所能做的改进，如果有人想使用其他模块来缩短代码，那么您也可以使用它们，我已经感谢那些想为此花费宝贵时间的人。其他初学者也会发现这很有帮助。

import pyinputplus as pyp


menu = True

# price of all ingredients
prices = {'wheat': 2, 'white': 1, 'sour dough': 3, 'chicken': 2, 'turkey': 3, 'ham': 2, 'tofu': 1,
          'cheddar': 1, 'swiss': 2, 'mozzarella': 3, 'mayo': 1, 'mustard': 1, 'lettuce': 1,
          'ketchup': 1}
while menu:
    # options to select bread, protein, cheese with inputMenu() method
    bread = pyp.inputMenu(['wheat', 'white', 'sour dough'],
                          prompt='Please select the type of bread you want for your sandwich: \n',
                          numbered=True)

    protein = pyp.inputMenu(['chicken', 'Turkey', 'Ham', 'Tofu'],
                            prompt='Which type of protein you would like: \n',
                            numbered=True)

    cheese = pyp.inputYesNo('Do you want Cheese in your sandwich?(Y/N)\n')
    cheese_type = ''
    if cheese == 'yes':
        cheese_type = pyp.inputMenu(['cheddar', 'swiss', 'mozzarella'], numbered=True)

    # using inputYesNo() for single ingredients with no further types
    mayo = pyp.inputYesNo('Do you want mayo?(Y/N) \n')
    mustard = pyp.inputYesNo('Do you want mustard?(Y/N) \n')
    lettuce = pyp.inputYesNo('Do you want lettuce?(Y/N) \n')
    ketchup = pyp.inputYesNo('Do you want tomato ketchup?(Y/N) \n')

    # using inputInt() and blockRegexes that do not allow negative integer, float or 0
    sandwichQT = pyp.inputInt('How much sandwiches you would like to order?\n',
                              blockRegexes=['[0|-|.]'])

    total_amount = 0

    # using for loop to print items, prices and adding their amount to total_amount variable
    for item, price in prices.items():
        if bread == item:
            print(f'Your sandwich ingredients and prices are as follows: \n'
                  f'{item}= {price}')
            total_amount += price

        if protein == item:
            print(f'{item}= {price}')
            total_amount += price

        if cheese_type == item:
            print(f'{item}= {price}')
            total_amount += price

    # for items that have yes and no values stored and also adding their amount to total
    if mayo == 'yes':
        print(f"mayo = {prices['mayo']}")
        total_amount += prices['mayo']

    if mustard == 'yes':
        print(f"mustard = {prices['mustard']}")
        total_amount += prices['mustard']

    if lettuce == 'yes':
        print(f"lettuce = {prices['lettuce']}")
        total_amount += prices['lettuce']

    if ketchup == 'yes':
        print(f"ketchup = {prices['ketchup']}")
        total_amount += prices['ketchup']

    # at the end printing total amount and how much sandwiches have been ordered
    print(f"sandwich cost x sandwich Qt ordered = {total_amount}x{sandwichQT} = "
          f"{total_amount*sandwichQT}")

    # confirming if the user need to reorder or user wants to confirm the order by simple yes/no
    # if user confirm by typing yes or y then menu will become false and while loop will terminate
    order_confirm = pyp.inputYesNo('Please confirm your order: (Y/N)\n')
    if order_confirm == 'yes':
        print('Please take your order number from the machine and you will be notified when '
              'its ready')
        menu = False

Answer 1

while True

首先，在Python中使用“标志”变量并不常见。与使用布尔变量控制while循环不同，您只需执行while True: ... break。

避免多ifs

您可能会注意到以下内容的重复结构：

print(f'{item}= {price}')
total_amount += price

在每个if下。这是因为你的逻辑颠倒了。您目前正在迭代所有可能的成分，并检查是否需要它们。但可能有许多没有使用的。更有意义的是，创建一个在使用的成分清单，然后只是把他们的价格在一个循环。这需要改变你保存酱汁的方式。我们将不将它们保存为'yes'，而是使用它们的名称来保存它们--以便与prices切分键匹配。

因此，我们将创建一个ingredients列表，并添加酱汁：

if pyp.inputYesNo('Do you want mayo?(Y/N) \n') == 'yes':
    ingredients.append('mayo')

现在，打印循环将是if-free：

print(f'Your sandwich ingredients and prices are as follows: \n')
for item in ingredients:
    price = prices[item]
    print(f'{item}= {price}')
    total_amount += price

全码

import pyinputplus as pyp

# price of all ingredients
prices = {'wheat': 2, 'white': 1, 'sour dough': 3, 'chicken': 2, 'turkey': 3, 'ham': 2, 'tofu': 1,
          'cheddar': 1, 'swiss': 2, 'mozzarella': 3, 'mayo': 1, 'mustard': 1, 'lettuce': 1,
          'ketchup': 1}

while True:
    ingredients = []
    # options to select bread, protein, cheese with inputMenu() method
    ingredients.append(pyp.inputMenu(['wheat', 'white', 'sour dough'],
                          prompt='Please select the type of bread you want for your sandwich: \n',
                          numbered=True))

    ingredients.append(pyp.inputMenu(['chicken', 'Turkey', 'Ham', 'Tofu'],
                            prompt='Which type of protein you would like: \n',
                            numbered=True))

    if pyp.inputYesNo('Do you want Cheese in your sandwich?(Y/N)\n')== 'yes':
        ingredients.append(pyp.inputMenu(['cheddar', 'swiss', 'mozzarella'], numbered=True))

    # using inputYesNo() for single ingredients with no further types
    if pyp.inputYesNo('Do you want mayo?(Y/N) \n') == 'yes':
        ingredients.append('mayo')
    if pyp.inputYesNo('Do you want mustard?(Y/N) \n') == 'yes':
        ingredients.append('mustard')
    if pyp.inputYesNo('Do you want lettuce?(Y/N) \n') == 'yes':
        ingredients.append('lettuce')
    if pyp.inputYesNo('Do you want tomato ketchup?(Y/N) \n') == 'yes':
        ingredients.append('ketchup')

    # using inputInt() and blockRegexes that do not allow negative integer, float or 0
    sandwichQT = pyp.inputInt('How much sandwiches you would like to order?\n',
                              blockRegexes=['[0|-|.]'])

    total_amount = 0
    # using for loop to print items, prices and adding their amount to total_amount variable
    print(f'Your sandwich ingredients and prices are as follows: \n')
    for item in ingredients:
        price = prices[item]
        print(f'{item}= {price}')
        total_amount += price

    # at the end printing total amount and how much sandwiches have been ordered
    print(f"sandwich cost x sandwich Qt ordered = {total_amount}x{sandwichQT} = "
          f"{total_amount*sandwichQT}")

    # confirming if the user need to reorder or user wants to confirm the order by simple yes/no
    # if user confirm by typing yes or y then menu will become false and while loop will terminate
    if pyp.inputYesNo('Please confirm your order: (Y/N)\n')== 'yes':
        print('Please take your order number from the machine and you will be notified when '
              'its ready')
        break