class Animal:def run(self):print('Running...')def sleep(self):print('Sleeping...')class Dog(Animal):def run(self):print('Dog is running...')def sleep(self):print('Dog is sleeping...')def Housekeep(self):print('Dog is housekeeping')d = Dog()d.run()
打印Dog is ...
下边再详细说明，
class A(object):def test(self):print('A...')class B(A):passclass C(B):passc = C()c.test()
打印A... 。
类B中加入方法test()后，
class A(object):def test(self):print('A...')class B(A):def test(self):print('B...')class C(B):passc = C()c.test()
打印B...
类C中加入方法test()后，
class A(object):def test(self):print('A...')class B(A):def test(self):print('B...')class C(B):def test(self):print('C...')c = C()c.test()
打印C... 。
当我们调用一个对象时，会有先去当前对象寻找是否有该方法，如果有直接调用；如果没有，则取当前对象的父类中寻找，如果有，直接调用父类中的方法，如果没有，则去父类的父类寻找，如果有直接调用，以此类推，直到找到，如果依然没有则报错 。
10.4 super()
父类中所有的方法都会被子类继承，包括特殊方法，如()等，也可以重写特殊方法 。
class Animal:def __init__(self,name):self._name = namedef run(self):print('Running...')def sleep(self):print('Sleeping...')@propertydef name(self):return self._name@name.setterdef name(self,name):self._name = nameclass Dog(Animal):def run(self):print('Dog is running...')def sleep(self):print('Dog is sleeping...')def Housekeep(self):print('Dog is housekeeping')d = Dog()d.run()
会抛出异常，: ()1: 'name'
因为初始化没有传入参数，因为父类初始化要传入name这个参数，子类也必须传入 。
传入参数后,
class Animal:def __init__(self,name):self._name = namedef run(self):print('Running...')def sleep(self):print('Sleeping...')@propertydef name(self):return self._name@name.setterdef name(self,name):self._name = nameclass Dog(Animal):def run(self):print('Dog is running...')def sleep(self):print('Dog is sleeping...')def Housekeep(self):print('Dog is housekeeping')d = Dog('erha')print(d.name)
打印erha
调用方法修改属性，
class Animal:def __init__(self,name):self._name = namedef run(self):print('Running...')def sleep(self):print('Sleeping...')@propertydef name(self):return self._name@name.setterdef name(self,name):self._name = nameclass Dog(Animal):def run(self):print('Dog is running...')def sleep(self):print('Dog is sleeping...')def Housekeep(self):print('Dog is housekeeping')d = Dog('erha')d.name = 'demu'print(d.name)
打印demu 。
如果需要在子类中定义新的属性时，即要扩展属性时，
class Animal:def __init__(self,name):self._name = namedef run(self):print('Running...')def sleep(self):print('Sleeping...')@propertydef name(self):return self._name@name.setterdef name(self,name):self._name = nameclass Dog(Animal):def __init__(self,name,age):self._name = nameself._age = agedef run(self):print('Dog is running...')def sleep(self):print('Dog is sleeping...')def Housekeep(self):print('Dog is housekeeping')@propertydef age(self):return self._age@age.setterdef age(self, age):self._age = aged = Dog('erha',10)print(d.name)print(d.age)