Can't access parent member variable in Python

问题

I'm trying to access a parent member variable from an extended class. But running the following code...

class Mother(object):
    def __init__(self):
        self._haircolor = "Brown"

class Child(Mother):
    def __init__(self): 
        Mother.__init__(self)   
    def print_haircolor(self):
        print Mother._haircolor

c = Child()
c.print_haircolor()

Gets me this error:

AttributeError: type object 'Mother' has no attribute '_haircolor'

What am I doing wrong?

回答1:

You're mixing up class and instance attributes.

print self._haircolor

回答2:

You want the instance attribute, not the class attribute, so you should use self._haircolor.

Also, you really should use super in the __init__ in case you decide to change your inheritance to Father or something.

class Child(Mother):
    def __init__(self): 
        super(Child, self).__init__()
    def print_haircolor(self):
        print self._haircolor

来源：https://stackoverflow.com/questions/10064688/cant-access-parent-member-variable-in-python