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Python Django Class-based Views Classy Views List and Detail

Dillon Reyna
Dillon Reyna
9,531 Points
Posted by Dillon Reyna
Dillon Reyna
9,531 Points

How do I "catch" a pk?

Unsure of what to do here - How am I meant to "catch" the pk?

articles/urls.py 
from django.conf.urls import url

from . import views

urlpatterns = [
    url(r'^$', views.ArticleList.as_view(), name="list"),
    url(r'^<pk>$', views.ArticleDetail.as_view(), name="detail"),
]
articles/views.py 
from django.views.generic import ListView, DetailView

from . import models

class ArticleList(ListView):
    model = models.Article

class ArticleDetail(DetailView):
    model = models.Article
articles/templates/articles/article_list.html 
<h1>Articles</h1>

<ul>
</ul>
articles/templates/articles/article_detail.html 
<h1>Article title</h1>
<p>By: Author name</p>

Article body with linebeaks

1 Answer

William Ennals
William Ennals
9,441 Points
William Ennals
William Ennals
9,441 Points

When they say "catch" a pk, they are referring to the use of parenthesis in the regular expression in the url. 

 url(r'^(?P<pk>\d+)/$', views.ArticleDetail.as_view(), name='detail')

Parentheses group the regex between them. They capture the text matched by the regex inside them into a numbered group that can be reused with a numbered backreference. They allow you to apply regex operators to the entire grouped regex. Check out this link for more information