如何使用模板标签创建“仅适用于选项表中没有 product_code 的产品的 p-tag”？

{% for option in option_object %}
{{option.product_code}}
{% if option.product_code == None %}}

<p> hello </p>

{% endif %}
{% endfor %}

我是这样写的，但它不起作用。除了上述之外，我们尝试了与 {% if not product.product_code == option.product_code %} 相同的方法，但仍未解决。

你怎么能只“在没有选项的产品上打印 p 标签”？

模型.py

class Product(models.Model):
    product_code = models.AutoField(primary_key=True)
    username = models.ForeignKey(Member, on_delete=models.CASCADE, db_column='username')
    category_code = models.ForeignKey(Category, on_delete=models.SET_NULL, null=True, related_name='products')
    name = models.CharField(max_length=200, db_index=True)
    slug = models.SlugField(max_length=200, db_index=True, unique=False, allow_unicode=True)
    image = models.ImageField(upload_to='products/%Y/%m/%d', blank=True)
    benefit = models.TextField()
    detail = models.TextField()
    target_price = models.IntegerField()
    start_date = models.DateField()
    due_date = models.DateField()
    created_at = models.DateTimeField(auto_now_add=True)

    class Meta:
        ordering = ['product_code']
        index_together = [['product_code', 'slug']]

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse('zeronine:product_detail', args=[self.product_code, self.slug])

class Option(models.Model):
    option_code = models.AutoField(primary_key=True)
    name = models.CharField(max_length=32)
    product_code = models.ForeignKey(Product, on_delete=models.CASCADE, db_column='product_code')

    def __str__(self):
        return self.name

    class Meta:
        ordering = ['option_code']

class Value(models.Model):
    value_code = models.AutoField(primary_key=True)
    option_code = models.ForeignKey(Option, on_delete=models.CASCADE, db_column='option_code', null=True)
    product_code = models.ForeignKey(Product, on_delete=models.CASCADE, db_column='product_code', null=True)
    name = models.CharField(max_length=32, null=True)
    extra_cost = models.IntegerField(null=True)

    def __str__(self):
        return self.name

    class Meta:
        ordering = ['value_code']

视图.py

def product_detail(request, id, product_slug=None):
    current_category = None
    categories = Category.objects.all()
    product = get_object_or_404(Product, product_code=id, slug=product_slug)
    designated_object = Designated.objects.filter(rep_price='True')
    element_object = Element.objects.all()
    photo_object = Photo.objects.all()
    option_object = Option.objects.all()
    value_object = Value.objects.all()


    return render(request, 'zeronine/detail.html', {'product': product,
                                                    'current_category': current_category,
                                                    'categories': categories,
                                                    'designated_object': designated_object,
                                                    'element_object': element_object,
                                                    'photo_object':photo_object,
                                                    'option_object': option_object,
                                                    'value_object': value_object,
                                                    })

解决方案

暂无回答