NoReverseMatch at /polls/ 在/polls/处发生了NoReverseMatch错误。

我正在根据Django教程制作一个网站。\n我遇到了一个错误：\n

\n在/polls/处找不到没有参数的“index”的反向匹配。尝试了1个模式：[\'$/\']。\n

\n错误\n跟踪显示：\n

跟踪：
File "/Users/XXX/django/django/core/handlers/exception.py" in inner
  35.             response = get_response(request)
File "/Users/XXX/django/django/core/handlers/base.py" in _get_response
  130.                 response = self.process_exception_by_middleware(e, request)
File "/Users/XXX/django/django/core/handlers/base.py" in _get_response
  128.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/Users/XXX/djangostudy/polls/views.py" in index
  23.         'questions': Question.objects.all(),
File "/Users/XXX/django/django/shortcuts.py" in render
  36.     content = loader.render_to_string(template_name, context, request, using=using)
File "/Users/XXX/django/django/template/loader.py" in render_to_string
  62.     return template.render(context, request)
File "/Users/XXX/django/django/template/backends/django.py" in render
  61.             return self.template.render(context)
File "/Users/XXX/django/django/template/base.py" in render
  175.                     return self._render(context)
File "/Users/XXX/django/django/template/base.py" in _render
  167.         return self.nodelist.render(context)
File "/Users/XXX/django/django/template/base.py" in render
  943.                 bit = node.render_annotated(context)
File "/Users/XXX/django/django/template/base.py" in render_annotated
  910.             return self.render(context)
File "/Users/XXX/django/django/template/loader_tags.py" in render
  155.             return compiled_parent._render(context)
File "/Users/XXX/django/django/template/base.py" in _render
  167.         return self.nodelist.render(context)
File "/Users/XXX/django/django/template/base.py" in render
  943.                 bit = node.render_annotated(context)
File "/Users/XXX/django/django/template/base.py" in render_annotated
  910.             return self.render(context)
File "/Users/XXX/django/django/template/loader_tags.py" in render
  155.             return compiled_parent._render(context)
File "/Users/XXX/django/django/template/base.py" in _render
  167.         return self.nodelist.render(context)
File "/Users/XXX/django/django/template/base.py" in render
  943.                 bit = node.render_annotated(context)
File "/Users/XXX/django/django/template/base.py" in render_annotated
  910.             return self.render(context)
File "/Users/XXX/django/django/template/defaulttags.py" in render
  447.             url = reverse(view_name, args=args, kwargs=kwargs, current_app=current_app)
File "/Users/XXX/django/django/urls/base.py" in reverse
  87.     return iri_to_uri(resolver._reverse_with_prefix(view, prefix, *args, **kwargs))
File "/Users/XXX/django/django/urls/resolvers.py" in _reverse_with_prefix
  488.         raise NoReverseMatch(msg)
异常类型：NoReverseMatch 在/polls/处
异常值：找不到没有参数的“index”的反向匹配。尝试了1个模式：['$/']

\n我在base.html中编写的与父级应用程序相同的代码如下：\n

{% load staticfiles %}
{% load bootstrap3 %}

  
    
    
    
    
    
    
    
    
    
    
    
  
  
    
    {% bootstrap_messages messages %}
    {% block contents %}{% endblock %}
    
    
    
    
    
    
  

\n父级目录的urls.py如下：\n

from django.conf.urls import include,url
from django.contrib import admin
from polls.views import index
urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^polls/',include('polls.urls')),
    url(r'^$/',index,name='index'),
]

\n子应用程序的urls.py如下：\n

from django.conf.urls import url
from django.views.generic import TemplateView
from . import views
app_name="polls"
urlpatterns = [
    url(r'^$',views.index,name='index'),
    url(r'(?P\d+)/$', views.detail, name='poll_detail'),
    url(r'(?P\d+)/vote$', views.vote, name='poll_vote'),
    url(r'(?P\d+)/results$', views.results, name='poll_results'),
    url(r'^$',TemplateView.as_view(template_name='app/index.html'),name='app_index'),
    url(r'^form$', views.form_test),
]

\n我真的不明白为什么会出现这个错误。指定的\"{% url \'index\' %}\"的方式是错误的吗？我该如何解决这个问题？\n我的views.py如下：\n

from django.shortcuts import render
from django.urls import reverse_lazy
from django.utils.html import mark_safe
from .models import Question
from django.http import HttpResponse
from django.shortcuts import Http404
from django.shortcuts import get_object_or_404,redirect
from .models import Choice
from django.views.generic import TemplateView
from django.views.generic import DetailView
from django.views.generic import ListView
from .forms import MyForm
from .forms import VoteForm
from django.views.generic import FormView
from django.views.generic.detail import SingleObjectMixin
from django.shortcuts import resolve_url
def index(request):
    return render(request,'polls/index.html',{
        'questions': Question.objects.all(),
    })
def vote(request,pk):
    question = get_object_or_404(Question,pk=pk)
    try:
        selected_choice = question.choice_set.get(pk=request.POST['choice'])
    except (KeyError,Choice.DoesNotExist):
        return render(request,'poll/detail.html',{
            'question':question,
            'error_message':"You didn't select a choice",
        })
    else:
        selected_choice.votes += 1
        selected_choice.save()
        return redirect('index')
    return redirect('poll_results', pk)
    # pass
def results(request,pk):
    obj = get_object_or_404(Question,pk=pk)
    return render(request,'polls/results.html',{
        'question':obj,
    })
class FormTest(FormView):
   form_class = MyForm
   template_name = 'polls/form.html'
   success_url = reverse_lazy('polls:index')
form_test = FormTest.as_view()
class Detail(SingleObjectMixin,FormView):
    model = Question
    form_class = VoteForm
    context_object_name = 'question'
    template_name = 'polls/detail.html'
    def get(self, request, *args, **kwargs):
        self.object = self.get_object()
        return super().post(request, *args, **kwargs)
    def post(self, request, *args, **kwargs):
        self.object = self.get_object()
        return super().post(request, *args, **kwargs)
    def get_form_kwargs(self):
        kwargs = super().get_form_kwargs()
        kwargs['question'] = self.object
        return kwargs
    def form_valid(self, form):
        form.vote()
        return super().form_valid(form)
    def get_success_url(self):
        return resolve_url('polls:results',self.kwargs['pk'])
detail = Detail.as_view()

\n我的目录如下：\n目录