python基础 类(四) 类的多继承

前言

接上篇单继承，这篇写写多继承的执行顺序

菱形结构的多继承

class AAA:
    def __init__(self):
        print('AAAinit')
        print('over AAA init')
        #print('AAA init ! ' + str(class_num))
        #self.class_num = class_num
        

    def talk_to_all(self):
        print("I am AAA!")


class A(AAA):
    #def __init__(self, class_num, *args):
    def __init__(self):
        print('A init')
        super().__init__()
        print('over A init')
        '''
        print('A init ! ' + str(class_num))
        print('A init ! ' + str(args))
        super(A, self).__init__(*args)
        self.class_num = class_num
        '''

    def talk_to_all(self):
        print("I am A!")

class B(AAA):
    #def __init__(self, class_num, *args):
    def __init__(self):
        print('B init')
        super().__init__()
        print('over B init')
        '''
        print('B init ! ' + str(class_num))
        print('B init ! ' + str(args))
        super(B, self).__init__(*args)
        self.class_num = class_num
        '''

    def talk_to_all(self):
        print("I am B!")


class C(A, B):
    #def __init__(self, class_num, *args):
    def __init__(self):
        print('C init')
        super().__init__()
        print('over c init')
        '''
        print("C Init ! " + str(class_num))
        print('C init ! ' + str(args))
        super(C, self).__init__(*args)
        self.class_num = class_num
        '''
        

    def talk_to_all(self):
        print("==== I am C! ====")
        super(B, self).talk_to_all()

test = C()
#test.talk_to_all()
print(C.__mro__)

执行结果

普通多继承

class A:
    #def __init__(self, class_num, *args):
    def __init__(self):
        print('A init')
        #super().__init__()
        print('over A init')

    def talk_to_all(self):
        print("I am A!")

class B:
    #def __init__(self, class_num, *args):
    def __init__(self):
        print('B init')
        #super().__init__()
        print('over B init')

    def talk_to_all(self):
        print("I am B!")


class C(A, B):
    #def __init__(self, class_num, *args):
    def __init__(self):
        print('C init')
        super().__init__()
        print('over c init')
        

    def talk_to_all(self):
        print("==== I am C! ====")
        super(B, self).talk_to_all()

test = C()
print(C.__mro__)

执行结果

可知，在多继承时,只是执行了第一个父类的构造函数

上面两种继承时执行的原型链