Django2.0手册:Django快捷函数



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)[source]

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()¶

render_to_response(template_name, context=None, content_type=None, status=None, using=None)[source]

Deprecated since version 2.0.

该函数之前引入了:func:render ,并类似地工作,只是它不使响应中的 request 可用。

redirect()¶

redirect(to, permanent=False, *args, **kwargs)[source]

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.

示例¶

You can use the redirect() function in a number of ways.

  1. 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):
        ...
        object = MyModel.objects.get(...)
        return redirect(object)
    
  2. 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')
    
  3. 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):
    ...
    object = MyModel.objects.get(...)
    return redirect(object, permanent=True)

get_object_or_404()¶

get_object_or_404(klass, *args, **kwargs)[source]

Calls get() on a given model manager,
but it raises Http404 instead of the model’s
DoesNotExist exception.

必选参数¶

klass
A Model class,
a Manager,
or a QuerySet instance from which to get
the object.
**kwargs
Lookup parameters, which should be in the format accepted by get() and
filter().

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):
    my_object = get_object_or_404(MyModel, pk=1)

此示例相当于:

from django.http import Http404

def my_view(request):
    try:
        my_object = 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)[source]

Returns the result of filter() on a
given model manager cast to a list, raising Http404 if
the resulting list is empty.

必选参数¶

klass
A Model, Manager or
QuerySet instance from which to get the
list.
**kwargs
Lookup parameters, which should be in the format accepted by get() and
filter().

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.")