python - 如何使用特定用户拥有的对象创建 ModelForm

Question

Possible Duplicate:
How do I filter ForeignKey choices in a Django ModelForm?

假设我有一些如下所示的模型:

from django.db import models
from django.contrib.auth.models import User

class Author(models.Model):
    first_name = models.CharField(max_length=100)
    last_name = models.CharField(max_length=100)
    owner = models.ForeignKey(User)

class Book(models.Model):
    title = models.CharField(max_length=100)
    authors = models.ManyToManyField(Author)
    owner = models.ForeignKey(User)

如果我为 Book 模型创建一个 ModelForm，用户可以从所有作者中进行选择，而不仅仅是他们拥有的作者。我如何为 Book 模型创建一个 ModelForm，让用户只选择她/他拥有的作者？

Answer 1

您可以覆盖模型表单的 __init__ 方法并限制作者 model choice field 的查询集.

class BookForm(forms.ModelForm):

    class Meta:
        model = Book
        # exclude the owner and set it in the view
        exclude = ('owner',) 

    def __init__(self, *args, **kwargs):
        super(BookForm, self).__init__(*args, **kwargs)
        if self.instance.owner:
            self.fields['author'].queryset = Author.objects.filter(owner=self.instance.owner)

在您看来，请确保使用已设置所有者的实例来实例化表单。例如，要添加一本书，它看起来像这样:

def add_book(request):
    book = Book(owner=request.owner)
    form = BookForm(data=request.POST or None, instance=book)
    if form.is_valid():
        book.save()
        return HttpResponseRedirect('/success-url/')
    return render(request, "my_template.html", {'form': form})