python类学习

创建关于汽车的类

class Cars():

    def __init__(self, brand, country):
        self.brand = brand
        self.country = country

    def show_brand(self):
        print(self.brand.title() + " is a popular automobile brand.")

    def show_country(self):
        print("Its headquater is in " + self.country.title() + ".")

my_car = Cars('toyota', 'Japan')
my_car.show_brand()
my_car.show_country()

输出

Toyota is a popular automobile brand.
Its headquater is in Japan.

列子

class Restaurant():
    def __init__(self, restaurant_name, cuisine_type):
        self.restaurant_name = restaurant_name
        self.cuisine = cuisine_type

    def describe_restaurant(self):
        print("There is a restaurant called " + self.restaurant_name.title() + ", its cuisine is " + self.cuisine.title() + ".")

    def open_restaurant(self):
        print("The restaurant " + self.restaurant_name.title() + " is opening...")

restaurant = Restaurant('xianghui xin', 'xiang cuisine')
restaurant.describe_restaurant()
print("I like " + restaurant.restaurant_name.title() + '.')
restaurant.open_restaurant()
print("Let's go " + restaurant.restaurant_name.title() + " and have lunch.")

输出

There is a restaurant called Xianghui Xin, its cuisine is Xiang Cuisine.
I like Xianghui Xin.
The restaurant Xianghui Xin is opening...
Let's go Xianghui Xin and have lunch.

类的默认属性值和修改方法1

class Car():
    def __init__(self, make, model, year):
        """初始化汽车描述属性"""
        self.make = make
        self.model = model
        self.year = year
        self.odometer_reading = 0

    def read_odometer(self):
        print("My car is " + self.make.title() + " " + self.model.title() + ", production date is " + str(self.year) + ".")
        print("This car has " + str(self.odometer_reading) + "KM mileage on it.")

my_new_car = Car('audi', 'a8l', 2019)
my_new_car.read_odometer()

my_new_car.odometer_reading = 1000
my_new_car.read_odometer()

输出

My car is Audi A8L, production date is 2019.
This car has 0KM mileage on it.
My car is Audi A8L, production date is 2019.
This car has 1000KM mileage on it.

修改方法2

class Car():
    """一次模拟汽车的简单尝试"""
    def __init__(self, make, model, year):
        self.make = make
        self.model = model
        self.year = year
        self.odometer_reading = 0

    def get_descriptive_name(self):
        long_name = str(self.year) + ' ' + self.make + ' ' + self.model
        return long_name.title()

    def read_odometer(self):
        print("This car has" + " " + str(self.odometer_reading) + "KM mileage on it.")

    def update_odometer(self, mileage):
        if mileage >= self.odometer_reading:
            self.odometer_reading = mileage
        else:
            print("You can't roll back an odometer !")

    def increment_odometer(self, miles):
        self.odometer_reading += miles

my_new_car = Car('audi', 'a8l', 2019)
get_descriptive_name = my_new_car.get_descriptive_name()
print(get_descriptive_name)
my_new_car.read_odometer()
my_new_car.update_odometer(100)
my_new_car.read_odometer()
my_new_car.update_odometer(90)
my_new_car.increment_odometer(10)
my_new_car.read_odometer()

输出

2019 Audi A8L
This car has 0KM mileage on it.
This car has 100KM mileage on it.
You can't roll back an odometer !
This car has 110KM mileage on it.

父类和子类

class Car():
    """传统汽车的属性"""
    def __init__(self, make, model, year):
        self.make = make
        self.model = model
        self.year = year
        self.odometer_reading = 0

    def get_descriptive_name(self):
        long_name = str(self.year) + ' ' + self.make + ' ' + self.model
        return long_name.title()

    def read_odometer(self):
        print("This car has" + " " + str(self.odometer_reading) + "KM mileage on it.")

    def update_odometer(self, mileage):
        if mileage >= self.odometer_reading:
            self.odometer_reading = mileage
        else:
            print("You can't roll back an odometer !")

    def increment_odometer(self, miles):
        self.odometer_reading += miles

class ElectricCar(Car):
    """电动汽车的独特属性"""
    def __init__(self, make, model, year):
        super().__init__(make, model, year)
        self.battery = 70

    def describe_battery(self):
        print("This car has a " + str(self.battery) + "-kWh battery.")

my_car = Car('audi', 'a8l', 2019)
get_my_car = my_car.get_descriptive_name()
print(get_my_car)
my_car.read_odometer()

my_tesla = ElectricCar('tesla', 'mode s', 2019)
get_my_tesla = my_tesla.get_descriptive_name()
print(get_my_tesla)
my_tesla.describe_battery()

输出

2019 Audi A8L
This car has 0KM mileage on it.
2019 Tesla Mode S
This car has a 70-kWh battery.