python - 如何在我的博客网站的顶部显示最新的帖子和评论？

Question

我已经成功地为评论和帖子制作了模型，它们在网页上正确显示，但我希望最新的帖子首先显示，评论也是如此。
View .py :

from django.shortcuts import render, HttpResponse, redirect
from blog.models import Post, BlogComment
from django.contrib import messages


# Create your views here.

def blogHome(request):
    allpost = Post.objects.all()
    context = {'allposts': allpost}
    return render(request, 'blog/blogHome.html', context)


def blogPost(request, slug):
    post = Post.objects.filter(slug=slug).first()
    comments = BlogComment.objects.filter(post=post)
    context = {'post': post, 'comments': comments}
    return render(request, 'blog/blogPost.html', context)

def postComment(request):
    if request.method == 'POST':
        comment = request.POST.get('comment')
        user = request.user
        postSno = request.POST.get("postSno")
        post = Post.objects.get(sno=postSno)

        comment = BlogComment(comment=comment, user=user, post=post)
        comment.save()
        messages.success(request, 'your comment has been added')

        return redirect(f"/blog/{post.slug}")

这是我希望首先显示最新帖子的博客主页
blogHome.html :

{% extends 'base.html' %}
{% block title %} blogs {% endblock title %}
{% block blogactive %}active {% endblock blogactive %}
{% block body %}

<h2 class="text-center my-4">blogs by everythingcs</h2>
<div class="container">
  {% for post in allposts %}
  <div class="col-md-6">
    <div class="row no-gutters border rounded overflow-hidden flex-md-row mb-4 shadow-sm h-md-250 position-relative">
      <div class="col p-4 d-flex flex-column position-static">
        <strong class="d-inline-block mb-2 text-primary">by-{{post.author}}</strong>
        <h3 class="mb-0">{{post.title}}</h3>
        <div class="mb-1 text-muted">Nov 12</div>
        <p class="card-text mb-auto">{{post.content|truncatechars:200}}</p>
        <div class="my-2">
          <a href="/blog/{{post.slug}}" role="button" class="btn btn-primary">More..</a>
        </div>
      </div>
    </div>
  </div>
  {% endfor %}
</div>

{% endblock body %}

最后是 模型.py 进一步引用:

from django.db import models
from django.contrib.auth.models import User
from django.utils.timezone import now
# Create your models here.


class Post(models.Model):
    sno = models.AutoField(primary_key=True)
    title = models.CharField(max_length=50)
    content = models.TextField()
    author = models.CharField(max_length=50)
    slug = models.SlugField(max_length=200)
    timeStamp = models.DateTimeField(blank=True)

    def __str__(self):
        return self.title + " by " + self.author


class BlogComment(models.Model):
    sno = models.AutoField(primary_key=True)
    comment = models.TextField()
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    post = models.ForeignKey(Post, on_delete=models.CASCADE)
    parent = models.ForeignKey('self', on_delete=models.CASCADE, null=True)
    timestamp = models.DateTimeField(default=now)

    def __str__(self):
        return self.comment[0:13] + "..." + "by " + self.user.username

简而言之，我想按时间对我的博客文章和博客评论进行排序，然后相应地显示它们。

Answer 1

您可以指定默认值 ordering [Django-doc]在 Meta [Django-doc]对象:

class Post(models.Model):
    sno = models.AutoField(primary_key=True)
    title = models.CharField(max_length=50)
    content = models.TextField()
    author = models.CharField(max_length=50)
    slug = models.SlugField(max_length=200)
    timestamp = models.DateTimeField(auto_now_add=True)

    class Meta:
        ordering = ['-timestamp']

    def __str__(self):
        return f'{self.title} by {self.author}'


class BlogComment(models.Model):
    sno = models.AutoField(primary_key=True)
    comment = models.TextField()
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    post = models.ForeignKey(Post, on_delete=models.CASCADE)
    parent = models.ForeignKey('self', on_delete=models.CASCADE, null=True)
    timestamp = models.DateTimeField(auto_now_add=True)

    class Meta:
        ordering = ['-timestamp']

    def __str__(self):
        return f'{self.comment[0:13]}... by {self.user.username}'

或者您可以明确订购:

def blogHome(request):
    allpost = Post.objects.order_by('-timestamp')
    context = {'allposts': allpost}
    return render(request, 'blog/blogHome.html', context)

Note: normally the name of the fields in a Django model are written in snake_case, not PerlCase, so it should be: timestamp instead of timeStamp.

Note: It is normally better to make use of the settings.AUTH_USER_MODEL [Django-doc] to refer to the user model, than to use the User model [Django-doc] directly. For more information you can see the referencing the User model section of the documentation.

Note: Django's DateTimeField [Django-doc]has a auto_now_add=… parameter [Django-doc]to work with timestamps. This will automatically assign the current datetimewhen creating the object, and mark it as non-editable (editable=False), suchthat it does not appear in ModelForms by default.