Django快捷函数¶
包 django.shortcuts
收集助手函数和“跨”多级mvc的类,换句话说,为了方便起见,这些函数/类引入受控耦合。
render()
¶
-
render
(request, template_name, context=None, content_type=None, status=None, using=None)[源代码]¶ 将给定的模板与给定的上下文字典组合在一起,并以渲染的文本返回一个
HttpResponse
对象。Django没有提供返回:class:~django.template.response.TemplateResponse 的快捷函数,因为:class:~django.template.response.TemplateResponse 的构造函数提供了与:func:`render()`相同的方便程度。
必选参数¶
request
- 用于生成此响应的请求对象。
template_name
- 要使用的模板的全名或模板名称的序列。如果给定一个序列,则将使用存在的第一个模板。有关如何查找模板的更多信息,请参见 template loading documentation 。
可选参数¶
context
- 要添加到模板上下文的值的字典。 默认情况下,这是一个空的字典。 如果字典中的值是可调用的,则视图将在渲染模板之前调用它。
content_type
- 用于结果文档的MIME类型默认为:设置:setting:DEFAULT_CONTENT_TYPE 设置的值。
status
- 响应的状态代码默认为“200”。
using
- 用于加载模板的模板引擎的 :setting:`NAME ` 。
例如¶
下面的示例使用MIME类型呈现模板``myapp/index.html`` application/xhtml+xml:
from django.shortcuts import render
def my_view(request):
# View code here...
return render(request, 'myapp/index.html', {
'foo': 'bar',
}, content_type='application/xhtml+xml')
此示例相当于:
from django.http import HttpResponse
from django.template import loader
def my_view(request):
# View code here...
t = loader.get_template('myapp/index.html')
c = {'foo': 'bar'}
return HttpResponse(t.render(c, request), content_type='application/xhtml+xml')
render_to_response()
¶
redirect()
¶
-
redirect
(to, permanent=False, *args, **kwargs)[源代码]¶ 将一个
HttpResponseRedirect
返回到传递的参数的适当URL。论点可以是:
- A model: the model's
get_absolute_url()
function will be called. - A view name, possibly with arguments:
reverse()
will be used to reverse-resolve the name. - An absolute or relative URL, which will be used as-is for the redirect location.
By default issues a temporary redirect; pass
permanent=True
to issue a permanent redirect.- A model: the model's
示例¶
You can use the redirect()
function in a number of ways.
By passing some object; that object's
get_absolute_url()
method will be called to figure out the redirect URL:from django.shortcuts import redirect def my_view(request): ... obj = MyModel.objects.get(...) return redirect(obj)
By passing the name of a view and optionally some positional or keyword arguments; the URL will be reverse resolved using the
reverse()
method:def my_view(request): ... return redirect('some-view-name', foo='bar')
By passing a hardcoded URL to redirect to:
def my_view(request): ... return redirect('/some/url/')
This also works with full URLs:
def my_view(request): ... return redirect('https://example.com/')
By default, redirect()
returns a temporary redirect. All of the above
forms accept a permanent
argument; if set to True
a permanent redirect
will be returned:
def my_view(request):
...
obj = MyModel.objects.get(...)
return redirect(obj, permanent=True)
get_object_or_404()
¶
-
get_object_or_404
(klass, *args, **kwargs)[源代码]¶ Calls
get()
on a given model manager, but it raisesHttp404
instead of the model'sDoesNotExist
exception.
必选参数¶
例如¶
The following example gets the object with the primary key of 1 from
MyModel
:
from django.shortcuts import get_object_or_404
def my_view(request):
obj = get_object_or_404(MyModel, pk=1)
此示例相当于:
from django.http import Http404
def my_view(request):
try:
obj = MyModel.objects.get(pk=1)
except MyModel.DoesNotExist:
raise Http404("No MyModel matches the given query.")
The most common use case is to pass a Model
, as
shown above. However, you can also pass a
QuerySet
instance:
queryset = Book.objects.filter(title__startswith='M')
get_object_or_404(queryset, pk=1)
The above example is a bit contrived since it's equivalent to doing:
get_object_or_404(Book, title__startswith='M', pk=1)
but it can be useful if you are passed the queryset
variable from somewhere
else.
Finally, you can also use a Manager
. This is useful
for example if you have a
custom manager:
get_object_or_404(Book.dahl_objects, title='Matilda')
You can also use
related managers
:
author = Author.objects.get(name='Roald Dahl')
get_object_or_404(author.book_set, title='Matilda')
Note: As with get()
, a
MultipleObjectsReturned
exception
will be raised if more than one object is found.
get_list_or_404()
¶
-
get_list_or_404
(klass, *args, **kwargs)[源代码]¶ Returns the result of
filter()
on a given model manager cast to a list, raisingHttp404
if the resulting list is empty.
必选参数¶
例如¶
The following example gets all published objects from MyModel
:
from django.shortcuts import get_list_or_404
def my_view(request):
my_objects = get_list_or_404(MyModel, published=True)
此示例相当于:
from django.http import Http404
def my_view(request):
my_objects = list(MyModel.objects.filter(published=True))
if not my_objects:
raise Http404("No MyModel matches the given query.")