Django 博客评论

Question

我无法在帖子的现有评论列表中添加新评论。这是模型：

class Comment(models.Model):
    post = models.ForeignKey(Post, on_delete=models.CASCADE, related_name='comments')
    body = models.TextField()
    commented_by = models.ForeignKey(User, on_delete=models.CASCADE)
    commented_on = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f'Commented by {self.commented_by} on {self.post}.'

这是视图：

def post_detail(request, id):
    post = Post.objects.get(id=id)
    comments = post.comments.all().order_by('-commented_on')
    total_comments = post.comments.all().count()
    form = CommentForm()

    if request.method == 'POST':
        form = CommentForm(request.POST, instance=post)
        if form.is_valid():
            instance = form.save(commit=False)
            instance.post = post
            instance.save()

    context = {
        'post' : post,
        'comments' : comments,
        'form' : form,
        'total_comments' : total_comments,
    }
    return render(request, 'blog/detail.html', context)

Answer 1

当您尝试保存新评论时，基本上您将错误的模型实例传递给表单：

form = CommentForm(request.POST, instance=post)
                                 ^^^^^^^^^^^^^

其实不用这样，你可以简单的声明表单实例：

form = CommentForm(request.POST)

这是一个小的重构代码：

def post_detail(request, id):
    post = Post.objects.get(id=id)
    form = CommentForm(request.POST or None)
    if request.method == 'POST':
        if form.is_valid():
            instance = form.save(commit=False)
            instance.post = post
            # instance.comment_by = request.user
            instance.save()
    comments = post.comments.all().order_by('-commented_on')
    total_comments = comments.count()
    context = {
        'post' : post,
        'comments' : comments,
        'form' : form,
        'total_comments' : total_comments,
    }
    return render(request, 'blog/detail.html', context)