Django模板中基于URL路径筛选关联模型的教程

# models.py
from django.db import models
from django.conf import settings
from django.core.validators import MaxValueValidator, MinValueValidator
from django.urls import reverse

class Destination(models.Model):
    name = models.CharField(max_length=255, primary_key=True)
    # ... 其他目的地字段

    def __str__(self):
        return self.name

class Attraction(models.Model):
    location = models.ForeignKey(
        Destination,
        on_delete=models.CASCADE,
    )
    name = models.CharField(primary_key=True, max_length=255)
    description = models.TextField(blank=False)
    address = models.TextField()
    rating = models.IntegerField(
        blank=False, validators=[MaxValueValidator(5), MinValueValidator(1)]
    )
    tags = models.TextField()
    numberReviews = models.IntegerField(default=1)
    date = models.DateTimeField(auto_now_add=True)
    author = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,
    )

    def __str__(self):
        return self.name

    def get_absolute_url(self):
        return reverse("attraction_detail", kwargs={"pk": self.pk})

{# attraction_list.html #}
{% for attraction in attraction_list %}
    {# 检查 attraction.location 的 ID 是否存在于当前 URL 的完整路径中 #}
    {% if attraction.location.id|stringformat:"s" in request.get_full_path %}
        <div class="card">
            <div class="card-header">
                <span class="fw-bold">
                    <a href="{{ attraction.get_absolute_url }}">{{ attraction.name }}</a>
                </span> &middot;
                <span class="text-muted">by {{ attraction.author }} |
                    {{ attraction.date }}</span>
            </div>
            <div class="card-body">
                {{ attraction.description }}
                {% if attraction.author.pk == request.user.pk %}
                <a href="{% url 'attraction_edit' attraction.pk %}">Edit</a>
                <a href="{% url 'attraction_delete' attraction.pk %}">Delete</a>
                {% endif %}
                <a href="{{ attraction.get_absolute_url }}">New Comment</a>
            </div>
            <div class="card-footer text-center text-muted">
                {% for attractioncomment in attraction.attractioncomment_set.all %}
                <p>
                    <span class="fw-bold">
                        {{ attractioncomment.author }}
                    </span>
                    {{ attractioncomment }}
                </p>
                {% endfor %}
            </div>
        </div>
    {% endif %}
{% endfor %}

# views.py
from django.shortcuts import render, get_object_or_404
from .models import Attraction, Destination

def destination_attraction_list(request, destination_id):
    destination = get_object_or_404(Destination, pk=destination_id)
    # 在视图层直接过滤，只获取属于当前目的地的景点
    attraction_list = Attraction.objects.filter(location=destination)
    # 或者更简洁地通过外键ID过滤
    # attraction_list = Attraction.objects.filter(location__pk=destination_id)

    context = {
        'destination': destination,
        'attraction_list': attraction_list,
    }
    return render(request, 'attraction_list.html', context)

# urls.py (in your destinations or attractions app)
from django.urls import path
from . import views

urlpatterns = [
    # ... 其他URL模式
    path('destinations/<str:destination_id>/attractions/', views.destination_attraction_list, name='destination_attraction_list'),
]

{# attraction_list.html (经过视图层过滤后) #}
{% for attraction in attraction_list %}
    <div class="card">
        {# 直接渲染，因为这里的 attraction_list 已经只包含当前目的地的景点 #}
        <div class="card-header">
            <span class="fw-bold">
                <a href="{{ attraction.get_absolute_url }}">{{ attraction.name }}</a>
            </span> &middot;
            <span class="text-muted">by {{ attraction.author }} |
                {{ attraction.date }}</span>
        </div>
        <div class="card-body">
            {{ attraction.description }}
            {% if attraction.author.pk == request.user.pk %}
            <a href="{% url 'attraction_edit' attraction.pk %}">Edit</a>
            <a href="{% url 'attraction_delete' attraction.pk %}">Delete</a>
            {% endif %}
            <a href="{{ attraction.get_absolute_url }}">New Comment</a>
        </div>
        <div class="card-footer text-center text-muted">
            {% for attractioncomment in attraction.attractioncomment_set.all %}
            <p>
                <span class="fw-bold">
                    {{ attractioncomment.author }}
                </span>
                {{ attractioncomment }}
            </p>
            {% endfor %}
        </div>
    </div>
{% endfor %}