未找到參數'（''，）'和關鍵字參數'{}'的'event_detail'的反轉。 1種模式（S）嘗試：[ '事件/（P <id> \\ d +）/ $']

Question

我下面這個教程http://slash4.net/blog/learn-django-in-4-hours，和我在/得到這個錯誤NoReverseMatch，當我運行http://localhost:8000/

urls.py

urlpatterns = [ 
    url(r'^admin/', include(admin.site.urls)), 
    url(r'^$', 'events.views.home', name='home'), 
    url(r'^events/$', 'events.views.list', name='event_list'), 
    url(r'^events/(?P<id>\d+)/$', 'events.views.detail', name='event_detail'), 

    url(r'^register/$', 'events.views.register', name='register'), 
    url(r'^login/$', auth_view.login, name='login', kwargs={'template_name': 'users/login.html'}), 
    url(r'^logout/$', auth_view.logout, name='logout', kwargs={'next_page': '/'}), 

    url(r'^events/join/(?P<event_id>\d+)/$', 'events.views.join', name='event_join'), 
    url(r'^events/cancel/(?P<event_id>\d+)/$', 'events.views.cancel', name='event_cancel'), 
    url(r'^user_event/(?P<user_id>\d+)/$', 'events.views.user_event', name='user_event') 
] 

的模板，模板渲染，在錯誤行過程中出現錯誤55

這是第55行：

<h4><a href="{% url 'event_detail' event_id %}">{{ event.title }}</a></h4> 

views.py

from datetime import datetime 
from django.shortcuts import render 

from django.contrib.auth.forms import UserCreationForm 
from django.http import HttpResponseRedirect 

from django.contrib.auth.decorators import login_required 
from django.core.urlresolvers import reverse 

from django.contrib.auth.models import User 

from .models import Event 

def home(request): 
    try: 
     event = Event.objects.filter(date__gt=datetime.now()).order_by('date')[:1][0] 
    except: 
     event = [] 
    return render(request, 'events/home.html', {'event': event}) 

def list(request): 
    event_list = Event.objects.all().order_by('date'); 
    return render(request, 'events/list.html', {'event_list': event_list}) 

def detail(request, id): 
    event = Event.objects.get(id=id) 
    joined = event.guest.filter(id=request.user.id) 
    return render(request, 'events/detail.html', {'event': event, 'joined': joined}) 

def register(request): 
    if request.method == 'POST': 
     form = UserCreationForm(request.POST) 
     if form.is_valid(): 
      new_user = form.save() 
      return HttpResponseRedirect("/") 
    else: 
     form = UserCreationForm() 
    return render(request, "users/register.html", { 
    'form': form, 
    }) 

@login_required 
def join(request, event_id): 
    try: 
     # already joined 
     event = Event.objects.get(id=event_id, guest=request.user) 
     message = "You have already joined this event" 
    except Event.DoesNotExist as e: 
     # Event exist but joined 
     try: 
      event = Event.objects.get(id=event_id) 
      event.guest.add(request.user) 
      event.save() 
      message = "You have joined this event" 
     except Event.DoesNotExist as e: 
      message = "Error on event joining" 

    url = "%s?msg=%s" % (reverse('event_detail', args=[event_id]), message) 
    return HttpResponseRedirect(url) 

@login_required 
def cancel(request, event_id): 
    try: 
     event = Event.objects.get(id=event_id, guest=request.user) 
     event.guest.remove(request.user) 
     event.save() 
     message = "Your request not to attend has been saved" 
    except Event.DoesNotExist as e: 
      message = "Error on cancelling your attedance on event" 

    url = "%s?msg=%s" % (reverse('event_detail', args=[event_id]), message) 
    return HttpResponseRedirect(url) 

def user_event(request, user_id): 
    event_list = Event.objects.filter(guest__id=user_id) 
    user = User.objects.get(id=user_id) 

    try: 
     event_list = Event.objects.filter(guest__id=user_id) 
     user = User.objects.get(id=user_id) 
    except: 
     event_list = [] 
     user = {} 

    print(event_list) 

    return render(request, 'events/user_event.html', {'event_list': event_list, 'user': user}) 

感謝UR支持

Answer 1

編輯1
我克隆了這個項目，問題是：
這個錯誤是由home.html 因爲視圖代碼：

def home(request): 
    try: 
     event = Event.objects.filter(date__gt=datetime.now()).order_by('date')[:1][0] 
    except: 
     event = [] 
    return render(request, 'events/home.html', {'event': event}) 

列表是空和沒有一個事件被傳遞到home.html的。

所以，只是改變了線55 home.html，到：

{%if event%} 
    <h4><a href="{% url 'event_detail' event.id %}">{{ event.title }}</a></h4> 
{%endif%} 

Answer 2

你沒有event_id變量在模板方面，你最想：

<h4><a href="{% url 'event_detail' id=event.id %}">{{ event.title }}</a></h4>