临时排序

Question

我已经创建了一个帖子列表，现在我想按发布日期订购此列表。如果我在视图中使用 order_by（-post_publishing_date）外壳程序向我显示此错误：

NameError：名称'post_publishing_date'未定义

models.py

class PostModel(models.Model):
    post_title = models.CharField(max_length=70)
    post_short_description = models.TextField(max_length=200)
    post_contents = models.TextField()
    post_publishing_date = models.DateTimeField(auto_now=False, auto_now_add=True)
    post_author = models.ForeignKey(AuthorModel, on_delete=models.CASCADE, related_name="connected_author")
    post_keyconcept = models.ManyToManyField(KeyConceptModel, related_name="connected_keyconcept")
    slug = models.SlugField(verbose_name="Slug", unique="True")
    post_highlighted = models.BooleanField(default=False)

    def __str__(self):
        return self.post_title

    def get_absolute_url(self): 
        return reverse("singlepostManuscriptusView", kwargs={"slug": self.slug})

    class Meta:
        verbose_name = "Articolo"
        verbose_name_plural = "Articoli"

views.py

class SinglePostGDV(DetailView):
    model = PostModel
    template_name = "manuscriptus_post_detail.html"


class ListPostGDV(ListView):
    model = PostModel
    template_name = "manuscriptus_home.html"
    queryset = PostModel.objects.filter().order_by(-post_publishing_date)

urls.py

urlpatterns = [
    path("it/blog/", ListPostGDV.as_view(), name="homeManuscriptusView"),
    path("it/blog/<slug:slug>/", SinglePostGDV.as_view(), name="singlepostManuscriptusView"), 
]

我做错了什么？

Answer 1

临时排序

Python是正确的。没有 identifier post_publishing_date，您通过字符串传递列的名称，因此：

class ListPostGDV(ListView):
    model = PostModel
    template_name = "manuscriptus_home.html"
    queryset = PostModel.objects.filter().order_by('-post_publishing_date')

在模型上定义固有顺序

请注意，您还可以在Meta类中为模型赋予“固有”顺序：

class PostModel(models.Model):
    post_title = models.CharField(max_length=70)
    post_short_description = models.TextField(max_length=200)
    post_contents = models.TextField()
    post_publishing_date = models.DateTimeField(auto_now=False, auto_now_add=True)
    post_author = models.ForeignKey(AuthorModel, on_delete=models.CASCADE, related_name="connected_author")
    post_keyconcept = models.ManyToManyField(KeyConceptModel, related_name="connected_keyconcept")
    slug = models.SlugField(verbose_name="Slug", unique="True")
    post_highlighted = models.BooleanField(default=False)

    def __str__(self):
        return self.post_title

    def get_absolute_url(self): 
        return reverse("singlepostManuscriptusView", kwargs={"slug": self.slug})

    class Meta:
        ordering = ['-post_publishing_date']
        verbose_name = "Articolo"
        verbose_name_plural = "Articoli"

如果您执行此操作，则对-post_publishing_date隐式排序对该模型的所有查询。因此，这意味着您不能“忘记”正确订购对象。

因此，您不必在视图中订购。当然，您只能定义一种这样的“固有”顺序，不清楚是否要在这里使用。

Answer 2

order_by参数应为字符串：

queryset = PostModel.objects.filter().order_by('-post_publishing_date')

订单发布日期

2 个答案:

临时排序

在模型上定义固有顺序