本文介绍了对内置对象的属性分配的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
这行得通:
class MyClass(object):
pass
someinstance = MyClass()
someinstance.myattribute = 42
print someinstance.myattribute
>>> 42
但这不是:
someinstance = object()
someinstance.myattribute = 42
>>> AttributeError: 'object' object has no attribute 'myattribute'
为什么?我有一种感觉，这与 object 作为内置类有关，但我觉得这并不令人满意，因为我在 MyClass 的声明中没有更改任何内容.
Why? I've got a feeling, that this is related to object being a built-in class, but I find this unsatisfactory, since I changed nothing in the declaration of MyClass.
推荐答案
Python 将属性存储在 dict 中.你可以给MyClass添加属性，看它有一个__dict__:
Python stores attributes in a dict. You can add attributes to MyClass, see it has a __dict__:
>>> class MyClass(object):
>>> pass
>>> dir(MyClass)
['__class__', '__delattr__', '__dict__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', '__weakref__']
重要的区别是 object 没有 __dict__ 属性.
The important difference is that object has no __dict__ attribute.
>>> dir(object)
['__class__', '__delattr__', '__doc__', '__format__', '__getattribute__', '__hash__', '__init__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__']
更详细的解释:
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