Django URLconf中的回调函数对象未调用 [英] The callback function object in Django URLconf is not called

问题描述

我正在 Django乍看之下租用Django | Django文档| Django

在引入URLconf时显示为：

When introducing URLconf It reads:

要设计对于应用程序的URL，您将创建一个称为URLconf的Python模块。应用程序的目录，其中包含URL模式和Python回调函数之间的简单映射。

To design URLs for an app, you create a Python module called a URLconf. A table of contents for your app, it contains a simple mapping between URL patterns and Python callback functions.

不过，回调函数是

mysite/news/urls.py
from django.conf.urls import url
from . import views
urlpatterns = [
    url(r'^articles/([0-9]{4})/$', views.year_archive),
]
print('callback funtion:',views.year_archive)

输出：

callback function: <function views.year_archive at 0x1039611e0>

因此它是一个未调用的函数对象。

So it a funtion object which is not called.

我想应该是 views.year_archive（）才能使其调用。

I suppose it should be views.year_archive() to enable it to call.

如果没有叫，它如何工作？我假设在父类中有一个装饰器来处理它。

If not called,how does it work? I assume there a decorator to process it in parent class.

我检查 url django.conf.urls | Django文档| Django

关键声明是：

 elif callable(view):
        return RegexURLPattern(regex, view, kwargs, name)

I继续探索 LocaleRegexProvider ， RegexURLPattern django.urls.resolvers | Django文档| Django 。
没有找到合适的代码来调用回调函数 views.year_archive

I dig on to explore LocaleRegexProvider, RegexURLPattern django.urls.resolvers | Django documentation | Django. No appopriate codes were found to call the callback function views.year_archive

其回调机制是什么

推荐答案

只要对给定的url模式发出请求，Django就会自动调用回调视图函数。

Django automatically calls the callback view function whenever a request is made to the given url pattern.

要了解其工作原理，请看以下示例：

To understand how it works, look at this example:

>>> def a():
        print("Called function a")

>>> def b():
        print("Called function b")

>>> def c(callback):
        # call the callback function like this
        callback()

>>> c(a)
Called function a
>>> c(b)
Called function b

基本上，这就是Django的 url 函数起作用。

Basically, this is how Django's url function works.

这篇关于Django URLconf中的回调函数对象未调用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！