Question

每次我尝试删除特定模型的实例时，都会收到错误：

object() takes no parameters

我查找了此错误消息，但所有帖子都指的是错误的 init 设置，我没有。

这让我疯了！知道是什么导致了这个吗？这是模型：

class CharacterSheet(models.Model):
    objects = ModelManager()

    save_name = models.CharField(max_length=150, blank=True, null=True)
    character_name = models.CharField(max_length=150, blank=True, null=True)

    root = models.TextField(
        default="{'lastId':'0', 'lastPlayerAddedId':'0', 'is_root':'true', 'type': 'section', 'direction': 'vertical'}")

    created = models.DateField(auto_now_add=True)
    edited = models.DateField(auto_now=True)

    color = models.IntegerField(default=random_color)

    template = models.ForeignKey('self', related_name="copies", on_delete=models.Empty, null=True)

    saved_on_profile = models.ForeignKey(Profile, on_delete=models.CASCADE, null=True)

    @property
    def root_json(self):
        return json.loads(self.root)

    def save(self, *args, **kwargs):
        """Save method override"""
        super(CharacterSheet, self).save(*args, **kwargs)
        for character in self.characters.all():
            character.save()

完整错误堆栈：

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/core/handlers/exception.py" in inner
  35.             response = get_response(request)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/core/handlers/base.py" in _get_response
  128.                 response = self.process_exception_by_middleware(e, request)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/core/handlers/base.py" in _get_response
  126.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/contrib/admin/options.py" in wrapper
  574.                 return self.admin_site.admin_view(view)(*args, **kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/utils/decorators.py" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/views/decorators/cache.py" in _wrapped_view_func
  44.         response = view_func(request, *args, **kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/contrib/admin/sites.py" in inner
  223.             return view(request, *args, **kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/utils/decorators.py" in _wrapper
  62.             return bound_func(*args, **kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/utils/decorators.py" in _wrapped_view
  142.                     response = view_func(request, *args, **kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/utils/decorators.py" in bound_func
  58.                 return func.__get__(self, type(self))(*args2, **kwargs2)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/contrib/admin/options.py" in delete_view
  1713.             return self._delete_view(request, object_id, extra_context)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/contrib/admin/options.py" in _delete_view
  1737.             [obj], opts, request.user, self.admin_site, using)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/contrib/admin/utils.py" in get_deleted_objects
  131.     collector.collect(objs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/contrib/admin/utils.py" in collect
  195.             return super().collect(objs, source_attr=source_attr, **kwargs)

File "/home/vvdrrltv/virtualenv/rolegate.com_rolegate__django/3.5/lib/python3.5/site-packages/django/db/models/deletion.py" in collect
  222.                         field.remote_field.on_delete(self, field, sub_objs, self.using)

Exception Type: TypeError at /admin/playerdata/charactersheet/1240/delete/
Exception Value: object() takes no parameters

Answer 1

你的问题在这里：

template = models.ForeignKey(
    'self', related_name="copies", 
    on_delete=models.Empty, null=True)

on_delete值无效;你需要选择one of the valid options。

例如，如果您要将引用替换为models.Empty，则必须改为使用models.SET(models.Empty)。

Answer 2

看看Django doc for ForeignKey.on_delete。可能的值有：

models.CASCADE
models.PROTECT
models.SET_NULL
models.SET_DEFAULT
models.SET（）
models.DO_NOTHING

您在字段models.Empty中使用的值（template）无效，可能是导致错误的原因

尝试删除模型实例时，object（）不带参数

2 个答案: