django - 为什么处理 POST 数据后重定向很重要？

Question

此代码来自Django documentation on forms :

from django.shortcuts import get_object_or_404, render
from django.http import HttpResponseRedirect, HttpResponse
from django.core.urlresolvers import reverse
from polls.models import Choice, Poll

def vote(request, poll_id):
    p = get_object_or_404(Poll, pk=poll_id)
try:
    selected_choice = p.choice_set.get(pk=request.POST['choice'])
except (KeyError, Choice.DoesNotExist):
    # Redisplay the poll voting form.
    return render(request, 'polls/detail.html', {
        'poll': p,
        'error_message': "You didn't select a choice.",
    })
else:
    selected_choice.votes += 1
    selected_choice.save()
    # Always return an HttpResponseRedirect after successfully dealing
    # with POST data. This prevents data from being posted twice if a
    # user hits the Back button.
    return HttpResponseRedirect(reverse('polls:results', args=(p.id,)))

我正在学习 Django 框架，但我不明白为什么在处理 POST 数据后重定向对于安全性很重要。

其实下面有相关的解释:

Always return an HttpResponseRedirect after successfully dealing with POST data. This prevents data from being posted twice if a user hits the Back button.

有人可以进一步解释一下吗？

Answer 1

这意味着用户可以通过点击F5或(Back-Sumbit)(Back-Sumbit)(Back-Sumbit)多次发布

如果不是返回重定向呢？

我认为它可以帮助防止灌溉。