python - Django - app.views.add 没有返回 HttpResponse 对象 -

Question

这是我在文件views.py中添加的 View

def add(request):
#se usaran las categorias para esto,se pasaran en locals()
categorias = Categoria.objects.all()
if request.method == "POST":
    form = EnlaceForm(request.POST)
    if form is valid():
        form.save()
        return HttpResponseRedirect("/")
    else:
        form = EnlaceForm()

    template = "form.html"
    return render_to_response(template, 
                            context_instance = RequestContext(request,locals()))

这是我的文件 urls.py，我在其中定义了“添加”url

from django.conf.urls import patterns, include, url
from django.contrib import admin
admin.autodiscover()

urlpatterns = patterns('',
    # Examples:
    #url(r'^$', 'app.views.hora_actual', name='hora_actual'),
    url(r'^$', 'app.views.home', name='home'),
    url(r'^minus/(\d+)$', 'app.views.minus', name='minus'),
    url(r'^plus/(\d+)$', 'app.views.plus', name='plus'),
    url(r'^categoria/(\d+)$', 'app.views.categoria', name='categoria'),
    url(r'^add/$','app.views.add', name="add"),

# url(r'^proyecto2/', include('proyecto2.foo.urls')),

# Uncomment the admin/doc line below to enable admin documentation:
    url(r'^admin/doc/', include('django.contrib.admindocs.urls')),

# Uncomment the next line to enable the admin:
    url(r'^admin/', include(admin.site.urls)),

)

在模板“form.html”中， token {% csrf_token %} 和 {{form.as_p}} 检查表单是否有效

<section id="contenido">
     <form method="post">
    <div id="form">
      {% csrf_token %}
    {{form.as_p}}
    <input type="submit">
 </form>
</div>
</section>

但是，当我在浏览器中调用 url 127:0.0.1:8000/add 时，我得到以下响应或输出:

ValueError at /add/

The view app.views.add didn't return an HttpResponse object.
Request Method: GET
Request URL:    http://127.0.0.1:8000/add/
Django Version: 1.5.2
Exception Type: ValueError
Exception Value:    
The view app.views.add didn't return an HttpResponse object.
Exception Location: C:\Python27\lib\site-packages\django\core\handlers\base.py in get_response, line 133
Python Executable:  C:\Python27\python.exe
Python Version: 2.7.5
Python Path:    
['C:\\django-projects\\tests\\proyecto2',
'C:\\Python27\\lib\\site-packages\\setuptools-0.9.6-py2.7.egg',
'C:\\Python27\\python27.zip',
'C:\\Python27\\DLLs',
'C:\\Python27\\lib',
'C:\\Python27\\lib\\plat-win',
'C:\\Python27\\lib\\lib-tk',
'C:\\Python27',
'C:\\Python27\\lib\\site-packages',
'C:\\Python27\\lib\\site-packages\\win32',
'C:\\Python27\\lib\\site-packages\\win32\\lib',
'C:\\Python27\\lib\\site-packages\\Pythonwin',
'C:\\Python27\\lib\\site-packages\\setuptools-0.6c11-py2.7.egg-info']
 Server time:   Thu, 12 Sep 2013 13:16:44 -0500

 Traceback Switch to copy-and-paste view

 C:\Python27\lib\site-packages\django\core\handlers\base.py in get_response
                raise ValueError("The view %s.%s didn't return an HttpResponse object."    % (callback.__module__, view_name)) ...
 ▶ Local vars

我知道所有基于函数的 View 都会接收一个请求对象并返回一个 HttpRespose 对象，但是，HttpResponse 和 render_to_response 对象之间有什么区别

从这个意义上说，我不知道我的问题是什么。感谢您的帮助。

Answer 1

您的渲染 render_to_response 向右缩进一级。

默认情况下， View 呈现为 GET (request.method=='GET')。您仅在 POST 部分中 return render_to_response(..) ，因此当请求处理 def add 时(第一次作为 GET 请求) )，没有返回 HttpResponse 对象。因此出现了错误。

def add(request):
    #se usaran las categorias para esto,se pasaran en locals()
    categorias = Categoria.objects.all()
    if request.method == "POST":
        form = EnlaceForm(request.POST)
        if form is valid():
            form.save()
            return HttpResponseRedirect("/")
    else:
        form = EnlaceForm()

    template = "form.html"
    return render_to_response(template, 
                                context_instance = RequestContext(request,locals()))

还要注意 else: block 的缩进。