Django 博客 - 評論系統

Question

我是 Django 的新手，我想知道如何使用基於類的視圖智能地鏈接評論和帖子系統。 這是“博客”應用程序中的“models.py”文件：

from django.db import models
from django.utils import timezone
from django.contrib.auth.models import User
from django.urls import reverse


class Post(models.Model):
    title = models.CharField(max_length=100)
    content = models.TextField()
    date_posted = models.DateTimeField(default=timezone.now)
    author = models.ForeignKey(User, on_delete=models.CASCADE)


    def __str__(self):
        return self.title

    
    def get_absolute_url(self):
        return reverse('post-detail', kwargs={'pk': self.pk})


class Comment(models.Model):
    post = models.ForeignKey(Post, related_name='comments', on_delete=models.CASCADE)
    title = models.CharField(max_length=100)
    author = models.ForeignKey(User, on_delete=models.CASCADE)
    content = models.TextField()
    date_posted = models.DateTimeField(default=timezone.now)

    class Meta:
        ordering = ['date_posted']

    def __str__(self):
        return '{} - {}'.format(self.author, self.date_posted)

我的“post_detail.html”模板顯示了特定的帖子，在這里我只想顯示帖子下的所有評論：

{% extends 'blog/base.html' %}

{% block content %}
    <article class="media content-section">
        <img class="rounded-circle article-img" src="{{ object.author.profile.image.url }}">
        <div class="media-body">
            <div class="article-metadata">
                <a class="mr-2" href="{% url 'user-posts' object.author.username %}">
                    {{ object.author }}
                </a>
                <small class="text-muted">{{ object.date_posted  | date:"F d, Y" }}</small>
                {% if object.author == user %}
                    <div>
                        <a class="btn btn-secondary btn-sm mt-1 mb-1" href="{% url 'post-update' object.id %}">Update</a>
                        <a class="btn btn-danger btn-sm mt-1 mb-1" href="{% url 'post-delete' object.id %}">Delete</a>
                    </div>
                {% endif %}
            </div>
            <h2 class="article-title">
                {{ object.title }}
            </h2>
            <p class="article-content">{{ object.content }}</p>
        </div>
    </article>
    <div>
        <strong><h2>Comments Section</h2></strong>
    </div>
{% endblock content %}

“views.py”文件如下所示：

from blog.forms import CommentForm
from django.db import models
from django.contrib.auth.mixins import LoginRequiredMixin
from django.contrib.auth.mixins import UserPassesTestMixin
from django.contrib.auth.models import User
from django.shortcuts import redirect, render
from django.shortcuts import get_object_or_404
from django.views.generic import ListView
from django.views.generic import DetailView 
from django.views.generic import CreateView
from django.views.generic import UpdateView
from django.views.generic import DeleteView
from .models import Post
from .models import Comment


def home(request):
    context = {
        'title': 'Home',
        'posts': Post.objects.all()
    }
    return render(request, 'blog/home.html', context)


class PostListView(ListView):
    model = Post
    template_name = 'blog/home.html'
    context_object_name='posts'
    ordering = ['-date_posted']
    paginate_by = 7


class UserPostListView(ListView):
    model = Post
    template_name = 'blog/user_posts.html'
    context_object_name='posts'
    paginate_by = 7

    def get_queryset(self):
        user = get_object_or_404(User, username=self.kwargs.get('username'))
        return Post.objects.filter(author=user).order_by('-date_posted')


class PostDetailView(DetailView):
    model = Post


def comment(request, pk):
    post = get_object_or_404(Post, pk=pk)
    if request.method == 'POST':
        form = CommentForm(request.POST)
        if form.is_valid():
            comment = form.save(commit=False)
            comment.post = post
            comment.save()
            return redirect('post-detail', pk=post.pk)
        else:
            form = CommentForm()
    return render(request, 'blog/post_detail.html', {'form': form})


class PostCreateView(LoginRequiredMixin, CreateView):
    model = Post
    fields = ['title', 'content']

    def form_valid(self, form):
        form.instance.author = self.request.user
        return super().form_valid(form)


class PostUpdateView(LoginRequiredMixin, UserPassesTestMixin, UpdateView):
    model = Post
    fields = ['title', 'content']

    def form_valid(self, form):
        form.instance.author = self.request.user
        return super().form_valid(form)

    def test_func(self):
        post = self.get_object()
        if self.request.user == post.author:
            return True
        return False



class PostDeleteView(LoginRequiredMixin, UserPassesTestMixin, DeleteView):
    model = Post
    success_url = '/'

    def test_func(self):
        post = self.get_object()
        if self.request.user == post.author:
            return True
        return False


def about(request):
    return render(request, 'blog/about.html', {'title': 'About'})

我知道一切都應該在PostDetailView class 中完成，但我不知道如何開始。 我將不勝感激任何想法或建議

Answer 1

你有一個從Comment到Post的外鍵，所以如果你有一個Post object，你可以通過post.comments.all()獲得所有相關的評論。

您可以直接在模板中執行此操作，只需省略括號即可。 這是一個用於說明的模板片段：

<div>
    <strong><h2>Comments Section</h2></strong>
    <ul>
    {% for comment in object.comments.all %}
        <li>{{ comment }} {{ comment.context }}</li>
    {% endfor %}
    </ul>
</div>

這種隱藏數據庫查詢以獲取模板中的評論。 如果您希望在視圖中執行查詢，可以覆蓋PostDetailView.get_context_data() ：

class PostDetailView（DetailView）：model = 發布

def get_context_data(self, **kwargs):
    ctx = super().get_context_datat(**kwargs)
    ctx["comments"] = ctx["object"].comments.all()
    return ctx

在這種情況下，模板中的 for 循環將如下所示：

{% for comment in object.comments.all %}