python - Python中的多重继承问题!

Question

为什么 c.print_a() 输出 'B'？

class A(object):
    def __init__(self):
        self.some_name = 'A'

    def print_a(self):
        print self.some_name

class B(object):
    def __init__(self):
        self.some_name = 'B'

    def print_b(self):
        print self.some_name

class C(A, B):
    def __init__(self):
        A.__init__(self)
        B.__init__(self)

if __name__ == '__main__':
    c = C()
    c.print_a()

---

class A(object):
    def __init__(self, some_name='A'):
        self.some_name = some_name

    def print_a(self):
        print self.some_name

class B(object):
    def __init__(self, some_name='B'):
        self.some_name = some_name

    def print_b(self):
        print self.some_name

class C(A, B):
    def __init__(self):
        A.__init__(self, some_name='AAAAA')
        B.__init__(self, some_name='BBBBB')

if __name__ == '__main__':
    c = C()
    c.print_a()

Answer 1

这里只有一个对象； some_name 属性在所有继承类的方法之间共享。您调用 A.__init__，将其设置为 A，然后调用 B.__init__，将其更改为 B .

另请注意，您错误地调用了基本方法；使用 super:

class A(object):
    def __init__(self):
        self.some_name = 'A'
        super(A, self).__init__()

    def print_a(self):
        print self.some_name

class B(object):
    def __init__(self):
        self.some_name = 'B'
        super(B, self).__init__()

    def print_b(self):
        print self.some_name

class C(A, B):
    def __init__(self):
        super(C, self).__init__()

if __name__ == '__main__':
    c = C()
    c.print_a()