python使用点操作符访问字典(dict)数据的方法

class DottableDict(dict):
 def __init__(self, *args, **kwargs):
 dict.__init__(self, *args, **kwargs)
 self.__dict__ = self
 def allowDotting(self, state=True):
 if state:
 self.__dict__ = self
 else:
 self.__dict__ = dict()
d = DottableDict()
d.allowDotting()
d.foo = 'bar'
print(d['foo'])
# bar
print(d.foo)
# bar
d.allowDotting(state=False)
print(d['foo'])
# bar from http://www.gxlcms.com
print(d.foo)
# AttributeError: 'DottableDict' object has no attribute 'foo'