访问已被覆盖的继承方法

Question

class A:
    def start(self):
        pass

class B(A):
    def start(self):
        super(A,self).start()

b = B()
b.start()

给出了这个错误：

Traceback (most recent call last):
  File "C:/Python32/a.py", line 10, in <module>
    b.start()
  File "C:/Python32/a.py", line 7, in start
    super(A,self).start()
AttributeError: 'super' object has no attribute 'start'

为什么？

Answer 1

如python doc中所述，super仅适用于新样式类，即：

  

注意 super（）仅适用于新式类。

所以你应该这样做：

class A(object):    # inherit from object to be a new style class
    def start(self):
        pass

class B(A):
    def start(self):
        super(B,self).start()   # the first arg of super is the current class

b = B()
b.start()