我有以下类(class):

class convert_to_obj(object): 
    def __init__(self, d): 
        for llist in d: 
            for a, b in llist.items(): 
                if isinstance(b, (list, tuple)): 
                    setattr(self, a, [obj(x) if isinstance(x, dict) else x for x in b]) 
                else: 
                    setattr(self, a, obj(b) if isinstance(b, dict) else b) 
 
    def is_authenticated(self): 
        username = self.username 
        password = self.password 
        if username and password: 
            return True 

我正在将字典转换为 obj，然后尝试访问 is_authenticated 方法，当我执行以下操作时:

new_array = [{'username': u'rr', 'password': u'something', }] 
user = convert_to_obj(new_array) 
user.is_authenticated() 

它返回一个错误说:

'convert_to_obj' object has no attribute 'is_authenticated' 

我不知道为什么会这样。希望其他人的眼睛能够指出我做错了什么。谢谢

请您参考如下方法:

@user2357112 是对的(而且很好，因为我不会看到它):

DO NOT USE TABS IN PYTHON ­— EVER!

也就是说，我对您的代码有几点意见。

首先:

class convert_to_obj(object): 

是一个非常糟糕的类名。不过，这将是一个很好的函数名称。你最好这样调用它，例如:

class DictObject(object): 

话虽这么说，我还是建议您使用现有工具来做这样的事情。有一个强大的叫namedtuple ，在 collections 模块中。为了做你的事，你可以这样做:

from collections import namedtuple 
 
# Create a class that declares the interface for a given behaviour 
# which will expect a set of members to be accessible 
class AuthenticationMixin(): 
    def is_authenticated(self): 
        username = self.username 
        password = self.password 
        # useless use of if, here you can simply do: 
        # return username and password 
        if username and password: 
            return True 
        # but if you don't, don't forget to return False below 
        # to keep a proper boolean interface for the method 
        return False 
 
def convert_to_object(d): # here that'd be a good name: 
    # there you create an object with all the needed members 
    DictObjectBase = namedtuple('DictObjectBase', d.keys()) 
    # then you create a class where you mix the interface with the 
    # freshly created class that will contain the members 
    class DictObject(DictObjectBase, AuthenticationMixin): 
        pass 
    # finally you build an instance with the dict, and return it 
    return DictObject(**d) 

这会给出:

>>> new_array = [{'username': u'rr', 'password': u'something', }] 
>>> # yes here I access the first element of the array, because you want 
>>> # to keep the convert_to_object() function simple.  
>>> o = convert_to_object(new_array[0]) 
>>> o 
DictObject(password='something', username='rr') 
>>> o.is_authenticated() 
True 

所有这些都更具可读性和易用性。

---

注意:对于要转换的字典列表，只需:

>>> objdict_list = [convert_to_object(d) for d in new_array] 
>>> objdict_list 
[DictObject(password='something', username='rr')] 

如果您使用的是对列表而不是字典:

>>> tup_array = [('username', u'rr'), ('password', u'something')] 
>>> {t[0]:t[1] for t in tup_array} 
{'password': 'something', 'username': 'rr'} 

因此您不需要在 __init__() 中做额外的工作。

HTH