1. 程式人生 > >上兩篇文件解釋了這段程式碼中的兩個疑問,order_by('-pub_date')[:5]和[q.question_text for q in latest_question_list]

上兩篇文件解釋了這段程式碼中的兩個疑問,order_by('-pub_date')[:5]和[q.question_text for q in latest_question_list]

我們還可以指定逆向排序,在前面加一個減號 - 字首:

?

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>>> Publisher.objects.order_by("-name")

[<Publisher: O'Reilly>, <Publisher: Apress>]

 

from django.http import HttpResponse

from .models import Question


def index(request):
    latest_question_list = Question.objects.order_by('-pub_date')[:5]
    output = ', '.join([q.question_text for q in latest_question_list])
    return HttpResponse(output)

# Leave the rest of the views (detail, results, vote) unchanged

逆向排序,

選擇陣列中的幾個元素, 

列表解析式,

https://docs.djangoproject.com/zh-hans/2.1/intro/tutorial03/#write-views-that-actually-do-something