9-9 电瓶升级
class Car():
def __init__(self, make, model, year):
self.make = make
self.model = model
self.year = year
self.read = 0
def describe(self):
long_name = str(self.year) + " " + self.make + " " + self.model + " "
return long_name.title()
def read(self):
print("Miles: " + str(self.read) + ".")
def update_read(self, x):
if x < self.read:
print("Invalid!")
else:
self.read = x
def increase_read(self, x):
if x < 0:
print("Invalid!")
else:
self.read += x
def fill_gas_tank(self):
print("Test")
class Battery():
def __init__(self, battery_size=70):
self.battery_size = battery_size
def describe_battery(self):
print("Battery: " + str(self.battery_size))
def get_range(self):
if self.battery_size == 70:
range = 240
elif self.battery_size == 85:
range = 270
message = "This car can go approximately " + str(range)
message += " miles on a full charge."
print(message)
def upgrade_battery(self):
if self.battery_size != '85':
self.battery_size = 85
class ElectricCar(Car):
def __init__(self, make, model, year):
super().__init__(make, model, year) # 继承Car类
self.battery = Battery() # 电瓶车的属性电池为类Battery的实例
def describe_battery(self):
print("Battery: " + str(self.battery_size))
def fill_gas_tank(self):
print("The car does not have a tank!")
my_tesla = ElectricCar('tesla', 'model s', 2016)
print(my_tesla.describe())
my_tesla.battery.describe_battery() # battery是类Battery()的一个对象
my_tesla.fill_gas_tank()
my_tesla.battery.get_range()
my_tesla.battery.upgrade_battery()
print(my_tesla.describe())
my_tesla.battery.describe_battery() # battery是类Battery()的一个对象
my_tesla.fill_gas_tank()
my_tesla.battery.get_range()