django ImageField - 'NoneType' 对象答案

【问题标题】：django ImageField - 'NoneType' objectdjango ImageField - 'NoneType' 对象
【发布时间】：2014-05-23 14:37:19
【问题描述】：

这是我的文件 forms.py

class RegisterForm(forms.ModelForm):
password = forms.CharField(widget=forms.PasswordInput())
password2 = forms.CharField widget=forms.PasswordInput())
username = forms.CharField(max_length=15)
email = forms.CharField(max_length=25)
avatar = forms.ImageField(required=False)

class Meta:
    model = User
    fields = ('username', 'email', 'password', 'password2', 'avatar')

def clean_password2(self):
    password = self.cleaned_data.get("password")
    password2 = self.cleaned_data.get("password2")
    if not password2:
        raise forms.ValidationError("error")
    if password != password2:
        raise forms.ValidationError("error2.")  

    return self.cleaned_data


def clean_avatar(self):
    image = self.cleaned_data['avatar']
    if image.size > 1*1024:
        raise forms.ValidationError("Image file too large ( > 1kb )")
    return image

和 models.py

class User(AbstractBaseUser):
username = models.CharField(max_length=15, unique = True)
email = models.CharField(max_length=25, unique = True)
reg_date = models.DateTimeField(_('reg_date'), default=timezone.now)
user_rating = models.IntegerField(default='0')
avatar = models.ImageField(upload_to='avatars', blank=True)

register.html

<form class="form" action='/auth/register/' method="post" enctype="multipart/form-data">
            {% csrf_token %}
            {{ form.as_p }}

            <div class="form-actions">
              <button type="submit" class="btn btn-info">Reg</button>

            </div>
        </form>

最后 views.py

def register(request):
context = RequestContext(request)
registered = False
if request.method == 'POST':
    form = RegisterForm(data=request.POST)
    if form.is_valid():
        user = form.save()
        user.set_password(user.password)
        if 'avatar' in request.FILES:
            user.avatar = request.FILES['avatar']
        user.save()
        registered = True
    else:
        print form.errors
else:
    form = RegisterForm()
return render_to_response('loginsys/register.html', {'form': form, 'registered': registered}, context)

我收到了这个错误：

 'NoneType' object has no attribute 'size'

    Request Method:     POST Request URL:   xxxxx/auth/register/ Django Version:    1.6.2 Exception Type:   AttributeError Exception Value:     

'NoneType' object has no attribute 'size'

Exception Location:     /home/max/xxxxx/loginsys/forms.py in clean_avatar, line 37



    loginsys/forms.py in clean_avatar

        37  if image.size > 1*1024:

...

▶ 局部变量

Traceback Switch to copy-and-paste view

/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py in get_response

                        response = wrapped_callback(request, *callback_args, **callback_kwargs)

    ...
▶ Local vars
/home/max/xxxxx/loginsys/views.py in register

            if form.is_valid():

    ...
▶ Local vars
/usr/local/lib/python2.7/dist-packages/django/forms/forms.py in is_valid

            return self.is_bound and not bool(self.errors)

    ...
▶ Local vars
/usr/local/lib/python2.7/dist-packages/django/forms/forms.py in errors

                self.full_clean()

    ...
▶ Local vars
/usr/local/lib/python2.7/dist-packages/django/forms/forms.py in full_clean

            self._clean_fields()

    ...
▶ Local vars
/usr/local/lib/python2.7/dist-packages/django/forms/forms.py in _clean_fields

                        value = getattr(self, 'clean_%s' % name)()

    ...
▶ Local vars
/home/max/xxxxx/loginsys/forms.py in clean_avatar

            if image._size > 1*1024:

    ...
▶ Local vars

为什么对象总是'NoneType'？如果我删除函数“def clean_avatar(self)”，则文件已成功保存。

【问题讨论】：

您可能应该重新措辞这个问题，并在开始时描述您正在尝试做什么以及遇到什么问题。这是一大堆毫无意义的代码，每个人都需要通读，无法真正知道你要做什么。
你在哪里调用 clean_avatar 函数？显示完整的回溯。另外，请注意您必须使用image._size。
我创建了一个注册表并尝试上传头像。头像已加载并保存，但我想检查图片的大小。在测试时，我总是得到这个错误。
Mihai Zamfir，我添加了

标签： django django-models

【解决方案1】：

1) 需要通过表单验证图片字段。

form = RegisterForm(data=request.POST, files=request.FILES)

2）您需要考虑用户没有选择图像，因为图像字段不是必需的。因此，您可以使用 clean 形式对其进行测试：

if image and image.size > 1*1024:

希望我能帮上忙。

【讨论】：