Django "NameError: name 'CarImageForm' is not defined" for self-referencing forms

Question

我正在关注 this tutorial 创建一个对象创建表单集。目标是允许通过外部对象连接到汽车对象的多个图像以单一形式上传。

图像使用一个表单集，每个字段有一个图像，动态创建了尽可能多的 'add another image' 字段。

运行服务器引发此错误："NameError: name 'CarImageForm' is not defined" 自引用包含定义的 class 时。

我查看了代码并发现了一些小的更正，但 none 似乎解决了这个问题。

forms.py

from django.forms import ModelForm, ImageField, CharField, TextInput

from .models import Car, Image, CustomUser

from django.contrib.auth.forms import AuthenticationForm, UserCreationForm, UserChangeForm
from django.forms.models import inlineformset_factory

from crispy_forms.helper import FormHelper
from crispy_forms.layout import Layout, Field, Fieldset, Div, HTML, ButtonHolder, Submit
from .custom_layout_object import Formset

class CarImageForm(ModelForm):

    class Meta:
        model = Image
        exclude = ()

    CarImageFormSet = inlineformset_factory(
        Car, Image, form=CarImageForm, fields=['car', 'image'], extra=1, can_delete=True
    )

class CreateCarForm(ModelForm):

    class Meta:
        model = Car
        exclude = ['seller']

    def __init__(self, *args, **kwargs):
        super(CarCreateForm, self).__init__(*args, **kwargs)
...  
            )
        )

Models.py（省略无关部分）

class Car(models.Model):
    manufacturer = models.ForeignKey('Manufacturer', on_delete=models.SET_NULL, null=True)
    car_model = models.CharField('Model', max_length=50, null=True)
    description = models.TextField(max_length=4000)
    vin = models.CharField('VIN', max_length=17, help_text='Enter the 17 character VIN number.', blank=True, null=True)
    mileage = models.IntegerField(verbose_name='Mileage')
    date_added = models.DateTimeField(auto_now_add=True)
    engine_displacement = models.CharField(default=2.0, max_length=3, help_text="Engine displacement in Liters (E.g. 2.0, 4.2, 6.3)")
    price = models.IntegerField(default=0)

    seller = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.SET_NULL, null=True, blank=True)

    id = models.UUIDField(primary_key=True, default=uuid.uuid4,
    help_text="Unique ID for this car")
...
    drivetrain = models.CharField(
        max_length=4,
        choices = DRIVETRAIN_OPTIONS,
        blank=True,
        default='4WD',
    )

...
    transmission = models.CharField(
        max_length=4,
        choices=TRANSMISSION_OPTIONS,
        blank=True,
        default='5MT')
...
    forced_induction = models.CharField(
        max_length=4,
        choices=FORCED_INDUCTION_OPTIONS,
        default='n',
        )

    # ensures that no model year  can be set in the future. 
    model_year = models.IntegerField(validators=[MaxValueValidator(int(datetime.date.today().year) + 1)], null=True)
...

    status = models.CharField(
        max_length=1,
        choices=AVAILABILITY_STATUS,
        blank=True,
        default='a',
        help_text="Car availability",
    )

    class Meta:
        ordering = ['-date_added']
        permissions = (("can_change_availability", "Mark car as sold"),)  
...

class Manufacturer(models.Model):
    manufacturer_name = models.CharField(max_length=20)
    country_of_origin = models.CharField(max_length = 20)

    def __str__(self):
        return f'{self.manufacturer_name}'

class Image(models.Model):
    car = models.ForeignKey(Car, on_delete=models.SET_NULL, null=True)
    image = models.ImageField(upload_to=image_directory_path)


    def __str__(self):
        return str(self.car.manufacturer) + ' ' + str(self.car.car_model) + ' image'

在抛出错误之前未达到视图，如果您需要查看该文件，请告诉我。

Answer 1

删除这些行中的缩进（一个制表符）：

    CarImageFormSet = inlineformset_factory(
        Car, Image, form=CarImageForm, fields=['car', 'image'], extra=1, can_delete=True
    )

Django "NameError: name 'CarImageForm' is not defined" for self-referencing forms

Django "NameError: name 'CarImageForm' is not defined" for self-referencing forms

forms

django

model

inline-formset

python-3.x