OperationalError at /1没有这样的列: auctions_comment.listing_id

Question

我对Django很陌生。我试图在一个拍卖网站上显示一个列表的所有评论，帮助我找到一种方法来显示一个列表的所有评论。

Mosdels.py

class Listing(models.Model):
    title = models.CharField(max_length=64, default="")
    starting_bid = models.CharField(max_length=64, default="$")
    description = models.TextField(default="")
    image_url = models.CharField(max_length=200, default="")
    date = models.DateTimeField(default=timezone.now)
    category = models.ForeignKey(Category, on_delete=models.CASCADE, default="")
    
    def __str__(self):
        return self.title


class Comment(models.Model):
    comment = models.TextField(default="")
    listing = models.ForeignKey(Listing, on_delete=models.CASCADE, related_name="comments", default="")
    user = models.ForeignKey(User, on_delete=models.CASCADE, related_name="comments", default="")

    def __str__(self):
        return f"{self.user} - {self.listing}"

views.py

def listing(request, listing_id):
    listing = Listing.objects.get(pk=listing_id)
    comments = listing.comments.all()
    return render(request, "auctions/listing.html", {
        "listing":listing,
        "comments":comments

    })

Answer 1

您要在模板中显示的_If可以使用如下所示：

{% for listing_item in listing %}
  <div>{{listing_item.title}}

  {% for comment in listing_item.comment_set.all %}
  <div>{{comment}}</div>
  {% endfor %}

  </div>
{% endfor %}

编辑:如果只从您的视图发送一个列表：

{{listing.title}}
{% for comment in listing.comment_set.all %}
  <div>{{comment}}</div>
{% endfor %}

EDIT2:注意到你在那里有一个相关的名字。

{{listing.title}}
{% for comment in listing.comments.all %}
  <div>{{comment}}</div>
{% endfor %}