Django :NoReverseMatch :/航天排放/组织/2/

Question

当我试图从list视图访问detail视图时，我会得到以下错误。

错误截图

奇怪的是，有些细节意见是可行的，有些则不行，我不明白问题在哪里。例如，下面是使用pk=1的组织的详细视图

组织细节视图

组织模型

class Organisation(models.Model):
    code = models.CharField(max_length=256, unique=True)
    name = models.CharField(max_length=256, null=True)
    english_name = models.CharField(max_length=256, null=True)
    location = models.CharField(max_length=256, null=True)
    country = models.ForeignKey('space_missions.Country',
                                on_delete=models.SET_NULL, null=True, blank=True)
    longitude = models.FloatField(null=True)
    latitude = models.FloatField(null=True)
    parent_organisation = models.ForeignKey('self', on_delete=models.SET_NULL, null=True, blank=True)

视图

class OrganisationDetail(generic.DetailView):
    model = models.Organisation


class OrganisationList(generic.ListView):
    model = models.Organisation

organisation_list.html

{% extends 'base.html' %}

{% block content %}
    <h1>Organisation List</h1>
    {% if organisation_list %}
        <ul>
            {% for organisation in organisation_list %}
                <li>
                    <a href="{% url 'space_missions:organisation-detail' pk=organisation.pk %}">
                        {{ organisation.name }}
                    </a>
                </li>
            {% endfor %}
        </ul>
    {% else %}
        <p>No organisation is stored in the database!</p>
    {% endif %}
{% endblock %}

organisation_detail.html

{% extends 'base.html' %}

{% block content %}
    <div class="container">
        <h1>{{ organisation.name }}'s details:</h1>
        <ul>
            <li><strong>Code: </strong> {{ organisation.code }}</li>
            <li><strong>English Name: </strong> {{ organisation.english_name }}</li>
            <li><strong>Location: </strong> {{ organisation.location }}</li>
            <li><strong>Country: </strong>
                <a href="{% url 'space_missions:country-detail' pk=organisation.country_id %}">
                    {{ organisation.country.name }}
                </a>
            </li>
            <li><strong>Longitude: </strong> {{ organisation.longitude }}</li>
            <li><strong>Latitude: </strong> {{ organisation.latitude }}</li>
            <li>
                <strong>Parent organisation: </strong>
                <a href="{% url 'space_missions:organisation-detail' pk=organisation.parent_organisation_id %}">
                    {{ organisation.parent_organisation.name }}
                </a>
            </li>
        </ul>
    </div>
{% endblock %}

urls.py

from django.urls import path
from . import views

app_name = 'space_missions'

urlpatterns = [
    path('countries/', views.CountryList.as_view(), name='countries'),
    path('country/<int:pk>/', views.CountryDetail.as_view(), name='country-detail'),
    path('astronauts/', views.AstronautList.as_view(), name='astronauts'),
    path('astronaut/<int:pk>/', views.AstronautDetail.as_view(), name='astronaut-detail'),
    path('organisations/', views.OrganisationList.as_view(), name='organisations'),
    path('organisation/<int:pk>/', views.OrganisationDetail.as_view(), name='organisation-detail'),
    path('engines/', views.EngineList.as_view(), name='engines'),
    path('engine/<int:pk>/', views.EngineDetail.as_view(), name='engine-detail'),
    path('stages/', views.StageList.as_view(), name='stages'),
    path('stage/<int:pk>/', views.StageDetail.as_view(), name='stage-detail'),
    path('launchvehicles/', views.LaunchVehicleList.as_view(), name='launch-vehicles'),
    path('launchvehicle/<int:pk>/', views.LaunchVehicleDetail.as_view(), name='launch-vehicle-detail'),
    path('missions/', views.MissionList.as_view(), name='missions'),
    path('mission/<int:pk>/', views.MissionDetail.as_view(), name='mission-detail'),
    path('selections/', views.SelectionList.as_view(), name='selections'),
    path('selection/<int:pk>/', views.SelectionDetail.as_view(), name='selection-detail')
]

Answer 1

当parent_organisation为None时，您的详细信息页将无法用pk=None找到组织详细信息的url。

<a href="{% url 'space_missions:organisation-detail' pk=organisation.parent_organisation_id %}">
                    {{ organisation.parent_organisation.name }}
                </a>

用if块包装代码

{% if organisation.parent_organisation_id %}
<a href="{% url 'space_missions:organisation-detail' pk=organisation.parent_organisation_id %}">
     {{ organisation.parent_organisation.name }}
</a>

{% endif %}