9.类
9.1创建和使用类
class Dog():
#类似c++数据的初始化
def __init__(self,name,age):
self.name = name
self.age = age
#类的函数
def sit(self):
print("小狗的名字是："+" "+self.name)
print("小狗的年龄是："+" "+str(self.age))
self相当于this指针
9.2创建示实例（对象）
first_dog = Dog('旺旺',6)
print(first_dog.name)
print(first_dog.age)
first_dog.sit()
9.3使用类和实例（对象）
class Car():
def __init__(self,make,model,year):
self.make = make
self.model = model
self.year = year
def get(self):
long_name = str(self.year)+''+self.make+''+self.model
return long_name
my_car = Car('s','d',5)
print(my_car.get())
9.3.1给属性指定默认值
class Car():
def __init__(self,make,model,year):
self.make = make
self.model = model
self.year = year
self.title = 0
def get(self):
long_name = str(self.year)+''+self.make+''+self.model
return long_name
my_car = Car('s','d',5)
print(my_car.get())
print(my_car.title)
9.4继承
一个类继承另一个类时，他将自动获得另一个类的所有属性和方法；原有的类称为父类，而父类被称为子类。
class Car():
def __init__(self,make,model,year):
self.make = make
self.model = model
self.year = year
self.title = 0
def get(self):
long_name = str(self.year)+''+self.make+''+self.model
return long_name
class ElectricCar(Car):
#super()继承父类的属性，并调用。
def __init__(self,make,model,year):
super().__init__(make,model,year)
my_ElectricCar = ElectricCar('s','d','f')
print(my_ElectricCar.make)