djangoでManyToMany関係を削除するにはどうすればよいですか。どのようにm2mを削除し、次に写真を削除しますかこれは以下の私のモデルですありがとう
class Picture(models.Model):
owner = models.ForeignKey(User,blank = True)
caption = models.CharField(max_length=150, blank=True, null=True)
image = ImageField(upload_to='images/',blank = True, null = True)
class Land(Properies):
photo = models.ManyToManyField(Picture,blank=True,related_name='Land_Pictures',null = True)
私はそれをこのように削除しようとしました
checked_list = []
start = 1
land_photos = sorted(list(land.photo.select_related()),reverse =True)
while start < 8:
photo = 'photo%s' % start
checked = form.cleaned_data[photo]
if checked != None:
checked_list.append(land_photos[start - 1])
start += 1
for a_foto in checked_list:
land.photo.remove(a_foto)
try:
a_foto.remove_all_file()
a_foto.delete()
except OSError:
pass
そして、私はこのようなエラーを受け取ります
Exception Type: AssertionError
Exception Value:
Picture object can't be deleted because its id attribute is set to None.