基于Django类的视图中的URL参数和逻辑(TemplateView)

Question

我不清楚在Django 1.5中如何最好地访问基于类的视图中的URL参数.

考虑以下:

视图:

from django.views.generic.base import TemplateView


class Yearly(TemplateView):
    template_name = "calendars/yearly.html"

    current_year = datetime.datetime.now().year
    current_month = datetime.datetime.now().month

    def get_context_data(self, **kwargs):
        context = super(Yearly, self).get_context_data(**kwargs)
        context['current_year'] = self.current_year
        context['current_month'] = self.current_month
        return context

URL配置:

from .views import Yearly


urlpatterns = patterns('',
    url(
        regex=r'^(?P<year>\d+)/$',
        view=Yearly.as_view(),
        name='yearly-view'
    ),
)

我想year在我的视图中访问参数,所以我可以像以下那样执行逻辑:

month_names = [
    "January", "February", "March", "April", 
    "May", "June", "July", "August", 
    "September", "October", "November", "December"
]

for month, month_name in enumerate(month_names, start=1):
    is_current = False
    if year == current_year and month == current_month:
        is_current = True
        months.append({
            'month': month,
            'name': month_name,
            'is_current': is_current
        })

如何最好地访问CBV中的url参数,如上面的子类,TemplateView以及理想情况下应该在哪里放置逻辑,例如.在一个方法？

Answer 1

要在基于类的视图中访问url参数,请使用self.args或者self.kwargs通过执行操作来访问它self.kwargs['year']

Answer 2

如果您传递URL参数,如下所示:

http://<my_url>/?order_by=created

您可以在基于类的视图中使用self.request.GET(它未显示self.args在内或中self.kwargs)来访问它:

class MyClassBasedView(ObjectList):
    ...
    def get_queryset(self):
        order_by = self.request.GET.get('order_by') or '-created'
        qs = super(MyClassBasedView, self).get_queryset()
        return qs.order_by(order_by)

Answer 3

我找到了这个优雅的解决方案,对于django 1.5或更高版本,正如这里所指出的:

Django基于泛型类的视图现在自动在上下文中包含一个视图变量.此变量指向您的视图对象.

在你的views.py中:

from django.views.generic.base import TemplateView    

class Yearly(TemplateView):
    template_name = "calendars/yearly.html"
    # Not here 
    current_year = datetime.datetime.now().year
    current_month = datetime.datetime.now().month

    # dispatch is called when the class instance loads
    def dispatch(self, request, *args, **kwargs):
        self.year = kwargs.get('year', "any_default")

    # other code

    # needed to have an HttpResponse
    return super(Yearly, self).dispatch(request, *args, **kwargs)

在这个问题中找到了调度解决方案.
由于视图已在Template上下文中传递,因此您并不需要关心它.在您的模板文件annual.html中,可以通过以下方式访问这些视图属性:

{{ view.year }}
{{ view.current_year }}
{{ view.current_month }}

你可以保持你的urlconf不变.

很高兴提到将信息输入到模板的上下文中会覆盖get_context_data(),因此它会以某种方式破坏django的action bean流.

Answer 4

到目前为止,我只能从get_queryset方法中访问这些url参数,尽管我只尝试使用ListView而不是TemplateView.我将使用url param在对象实例上创建属性,然后在get_context_data中使用该属性来填充上下文:

class Yearly(TemplateView):
    template_name = "calendars/yearly.html"

    current_year = datetime.datetime.now().year
    current_month = datetime.datetime.now().month

    def get_queryset(self):
        self.year = self.kwargs['year']
        queryset = super(Yearly, self).get_queryset()
        return queryset

    def get_context_data(self, **kwargs):
        context = super(Yearly, self).get_context_data(**kwargs)
        context['current_year'] = self.current_year
        context['current_month'] = self.current_month
        context['year'] = self.year
        return context

Answer 5

仅使用 Python 装饰器来使这变得易于理解如何：

class Yearly(TemplateView):

    @property
    def year(self):
       return self.kwargs['year']