Question

## class restaurant ##

实施超类

class Restaurant():
def __init__(self, restaurant_name, cuisine_type):
    self.restaurant_name = restaurant_name
    self.cuisine_type = cuisine_type 
def describe_restaurant(self):
    print('This restaurant is called ' + self.restaurant_name + '.')
    print('This restaurant serves dishes acoording to ' + self.cuisine_type + '.')
def open_restaurant(self, hours):
    self.hours = hours
    print(self.restaurant_name.title() + ' is opened ' + str(hours) + '!')

class IceCreamStand(Restaurant):
def __init__(self, restaurant_name, cuisine_type):
    super().__init__(restaurant_name, cuisine_type)
    self.restaurant_name = restaurant_name
    self.cuisine_type = cuisine_type
    flavours = ['chocolate', 'vanilia', 'strawberry', 'lime', 'orange']
def flavours(self):
    print('Available flavours: ')
    for flavour in flavours:
        print(flavour)
IceCreamStand  = Restaurant(' Matt IceCream ', 'ice creams')
IceCreamStand.describe_restaurant()
IceCreamStand.flavours()

Answer 1

在其他初学者到来尝试用Python理解OOP中的属性错误/按大小顺序处理这些错误时，请关闭此循环：

检查您的缩进-方法需要在一个类中缩进（见下文）
继承的属性无需重新实例化（即 IceCreamStand 中的餐厅名称和美食类型无需在对super().__init__的调用之外进行实例化将它们添加到 Restaurant 类的__init__方法，并使其在 IceCreamStand 类中可以访问）
传递给方法的参数应像常规函数一样单独引用，除非您有意在调用方法时实例化属性（与创建对象并调用__init__方法相反））

有关更改/运行代码，请参见下文：

class Restaurant:

    def __init__(self, restaurant_name, cuisine_type):
        self.restaurant_name = restaurant_name
        self.cuisine_type = cuisine_type

    def describe_restaurant(self):
        print('This restaurant is called ' + self.restaurant_name + '.')
        print('This restaurant serves dishes acoording to ' + self.cuisine_type + '.')

    def open_restaurant(self, hours):
        print(self.restaurant_name.title() + ' is opened ' + str(hours) + '!')


class IceCreamStand(Restaurant):

    def __init__(self, restaurant_name, cuisine_type):
        super().__init__(restaurant_name, cuisine_type)

        self.flavours = \
            ['chocolate', 'vanilia', 'strawberry', 'lime', 'orange']

    def flavours(self):
        print('Available flavours: ')
        for flavour in self.flavours:
            print(flavour)


stand = IceCreamStand(' Matt IceCream ', 'ice creams')
stand.describe_restaurant()
stand.flavours()

Answer 2

因为Restaurant确实没有属性flavours; IceCreamStand确实，或者至少做过，直到您使用Restaurant IceCreamStand = Restaurant(...)的实例替换了该类。

使用不同的变量名称（类名为camel-case，对象为初始小写的snake-case），并创建IceCreamStand的实例。

ice_cream_stand = IceCreamStand(' Matt IceCream ', 'ice creams')

AttributeError：'Restaurant'对象没有属性'flavors' - 为什么？

2 个答案: