django-selectable 表单验证和模型表单过滤器查询集

Question

我使用 django-selectable 进行自动完成，我需要模型表单验证

所以我在 forms.py

中进行了验证

def clean(self):
    cl_title = Color.objects.values_list('title',flat=True)
    if self.cleaned_data.get('color') != cl_title:
        raise forms.ValidationError('this color is not found in the database')
    return self.cleaned_data

我产生了一个错误

 Request Method:    POST
 Exception Type:    ValueError
 Exception Value: Cannot assign "<Color: awffawfwa>": "Color" instance isn't saved in the database.

没用详情见下方

models.py

class Color(models.Model):
    title = models.CharField('color title', max_length=100)
    user = models.CharField(User)
    description = models.TextField('description')

    def __str__(self):
        return self.title

class Item(models.Model):
    user = models.ForeignKey(User)
    color = models.ForeignKey(Color)
    # ... some logic

    def __str__(self):
        return self.color.title

lookups.py

from selectable.base import ModelLookup
from selectable.registry import registry
from .models import Color

class ColorLookup(ModelLookup):
    model = Book
    search_fields = ('title__icontains',)

registry.register(ColorLookup)

forms.py

from django import forms
from .models import Color
import selectable.forms as selectable
from .lookups import BookLookup

class ItemSelectForm(forms.ModelForm):
    color = selectable.AutoCompleteSelectField(
    lookup_class = ColorLookup,
    allow_new = True,
    label= 'select',
    required = True,
)

class Meta:
    model = Color
    fields = ('color',)

def clean(self):
    cl_title = Color.objects.values_list('title',flat=True)
    if self.cleaned_data.get('color') != cl_title:
        raise forms.ValidationError('this color is not found in the database')
    return self.cleaned_data

但是它不起作用，你能帮我吗，如何更正这个错误？提前致谢 ;)

Answer 1

values_list 将 return 一个颜色列表，所以你的单个值永远不会等于这个数组，你需要检查你的颜色不在这个列表中（如果它真的是一个列表你需要..)

您也可以将此逻辑分离到一个单独的颜色清理方法中。

def clean_color(self):
    color = self.cleaned_data.get('color')
    cl_title = Color.objects.values_list('title',flat=True)
    if color not in cl_title:
        raise forms.ValidationError('this color is not found in the database')
    return color

或者，您可能更喜欢

if not Color.objects.filter(title=color).exists():

这是一个更高效的查询，因为它return 数据库中没有任何不需要的值。

django-selectable 表单验证和模型表单过滤器查询集

django-selectable forms validation and model forms filter queryset

django

django-models

django-forms

python-2.7