首页 > 解决方案 > 为 DeleteView 类编写的额外函数不起作用

问题描述

我添加了一个功能,如果帖子被用户删除,如果有上传的照片就会被删除,但该功能不起作用。

我的观点:

class NewsDeleteView(LoginRequiredMixin, UserPassesTestMixin, DeleteView):
    model = News
    template_name = 'news/news_delete.html'
    success_url = reverse_lazy('news_list')

    def delete_header_image(self, pk):
        news = get_object_or_404(News, id = pk)
        header_image = news.header_image
        if header_image is not None:
            os.remove(str(header_image))
            return HttpResponseRedirect(reverse('news_list'))
        else:
            return HttpResponseRedirect(reverse('news_list'))

    def test_func(self):
        obj = self.get_object()
        if self.request.user.has_perm('news.all') or self.request.user.has_perm('news.delete_news') or obj.author == self.request.user:
            return True 

网址:

urlpatterns = [
    path('<int:pk>/delete', NewsDeleteView.as_view(), name='news_delete'),
] 

楷模:

def get_header_image_filepath(self, filepath):
    return f'images/news/header/{self.author.id}/{self.header_image}'


class News(models.Model):
    title = models.CharField(max_length=255)
    header_image = models.ImageField(null=True, blank=True, upload_to=get_header_image_filepath)
    body = RichTextUploadingField()
    datetime = models.DateTimeField(auto_now_add=True)
    author = models.ForeignKey(
        AUTH_USER_MODEL,
        on_delete=models.CASCADE,
    )
    def __str__(self):
        return self.title

    def get_absolute_url(self):
        return reverse("news_detail", args=[str(self.id)])

标签: djangodjango-modelsdjango-viewsdjango-urls

解决方案


基于类的视图不能神奇地工作。他们已经编写了一些方法,这些方法被调用来执行操作。因此,您编写一个方法delete_header_image并不意味着它会被自动调用。相反,您应该覆盖将在内部调用的类的一些合适的方法。对于DeleteView执行删除的方法是delete,因此您应该覆盖它。此外,该条件if header_image is not None将不起作用,因为即使没有文件也不会表示它,None而是您应该简单地编写if header_image以进行检查。此外,无需手动删除,只需调用ieldFile.delete[Django Docs]

class NewsDeleteView(LoginRequiredMixin, UserPassesTestMixin, DeleteView):
    model = News
    template_name = 'news/news_delete.html'
    success_url = reverse_lazy('news_list')

    def delete(self, request, *args, **kwargs):
        object = self.get_object()
        if object.header_image:
            object.header_image.delete(save=False)
        return super().delete(request, *args, **kwargs)

    def test_func(self):
        obj = self.get_object()
        if self.request.user.has_perm('news.all') or self.request.user.has_perm('news.delete_news') or obj.author == self.request.user:
            return True

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