python私有变量_如何使Python无法访问私有变量？

class Car(object):

def __init__(self, color, engine, oil):

self.color = color

self.__engine = engine

self.__oil = oil

a = Car('black', 'a cool engine', 'some cool oil')

We assume that __engine and __oil variables are private which means I cannot access them through a call like a.__engine. However, I can use __dict__ variable to access and even change those variables.

# Accessing

a.__dict__

{'_Car__engine': 'a cool engine', 'color': 'black', '_Car__oil': 'some cool oil'}

# Changing

a.__dict__['_Car__engine'] = "yet another cool engine"

a.__dict__

{'_Car__engine': 'yet another cool engine', 'color': 'black', '_Car__oil': 'some cool oil'}

The problem is simple. I want private variables to be accessed and changed only inside the class.

解决方案

What you are trying to do is not possible in Python.

“Private” instance variables that cannot be accessed except from inside an object don’t exist in Python.