Python中要想定义的方法或者变量只能在类内部使用不被外部使用,可以在方法和变量前面加两个下划线,让其变为私有方法或私有变量。类外部可以通过 ”_类名__私有属性(方法)名“ 访问私有属性(方法)。
class Person:
__work = 'teacher'
def __init__(self,name,age):
self.name = name
self.__age = age
def run(self):
print(self.__age,self.__work)
def __eat(self):
print('1111')
__work是私有类变量,类外是无法访问的
if __name__ == '__main__':
print(Person.__work)
Traceback (most recent call last): File "C:/Users/wangli/PycharmProjects/Test/test/test.py", line 20, in <module> print(Person.__work)AttributeError: type object 'Person' has no attribute '__work'
__work是私有类变量,类外类实例对象是无法访问的
if __name__ == '__main__':
test1 = Person('王大力','22')
print(test1.__work)Traceback (most recent call last): File "C:/Users/wangli/PycharmProjects/Test/test/test.py", line 21, in <module> print(test1.__work)AttributeError: 'Person' object has no attribute '__work'
__age是私有实例变量,类外类实例对象是无法访问的
if __name__ == '__main__':
test1 = Person('王大力','22')
print(test1.__age)Traceback (most recent call last): File "C:/Users/wangli/PycharmProjects/Test/test/test.py", line 21, in <module> print(test1.__age)AttributeError: 'Person' object has no attribute '__age'
__work是私有类变量,__age是私有实例变量,类内是可以访问的
if __name__ == '__main__':
test1 = Person('王大力','22')
test1.run()22 teacher
Process finished with exit code 0
__eat()是私有方法,类外是无法访问的
if __name__ == '__main__':
test1 = Person('王大力','22')
print(test1.__eat())Traceback (most recent call last): File "C:/Users/wangli/PycharmProjects/Test/test/test.py", line 21, in <module> print(test1.__eat())AttributeError: 'Person' object has no attribute '__eat'
__work是私有类变量,__age是私有实例变量,__eat()是私有方法,类外部可以通过 ”_Person___私有属性(方法)名“ 访问私有属性(方法)
if __name__ == '__main__':
print(Person._Person__work)
test1 = Person('王大力','22')
print(test1._Person__work)
print(test1._Person__age)
test1._Person__eat()
teacherteacher221111
Process finished with exit code 0