TypeError at /无法解压不可迭代的NoneType对象（Django）

Question

我正在尝试在我的 Django 项目上建立一个系统，用户可以在主（索引）页面上对各个帖子发表评论。但是，我在尝试将评论自动连接到帖子时遇到了问题。

这是我在views.py中尝试的代码：

from django.core import paginator
from django.shortcuts import render, redirect, get_object_or_404
from django.http import HttpResponse
from .models import *
from django.views.generic import ListView, CreateView, UpdateView
from django.views.generic.detail import DetailView
from .forms import *
from django.contrib.auth.forms import UserCreationForm
from django.contrib.auth import login
from django.core.paginator import Paginator
from django.views import View
import random

def index(request, pk=None, *args, **kwargs):
    postdata = Post_Data.objects.all()
    profiledata = ProfileData.objects.all()
    likedata = Like.objects.all()
    dislikedata = Dislike.objects.all()
    comment = PostComment.objects.all()
    postid = Post_Data.objects.get(pk)   


    # Initialize the comment form
    if request.method == 'POST':
        comment_form = PostCommentForm(request.POST)
        if comment_form.is_valid():
            post = comment_form.save(commit=False)
            post.user = request.user
            post.save()
            return redirect('/')
    else:
        comment_form = PostCommentForm()  # Create an empty form

    # Pass the comment form to the template context
    return render(request, 'index.html', {
        'title': 'RoamTrip',
        'postdata': postdata,
        'profiledata': profiledata,
        'likedata': likedata,
        'dislikedata': dislikedata,
        'comment': comment,
        'comment_form': comment_form  # Make sure this is included
    })

models.py：

from django.contrib import admin
from django.db import models
from django.urls import reverse
from django.contrib.auth.models import User
from django.contrib.auth import get_user_model
from django.conf import settings
from .validators import validate_file_extension

# Create your models here.

class Post_Data (models.Model):
    user = models.ForeignKey(
        settings.AUTH_USER_MODEL,
        on_delete=models.CASCADE,  # Set the appropriate behavior here
        null=True
    )
    time_data = models.DateTimeField(help_text='Enter Time of Upload Here:', auto_now_add=True)
    text_data = models.TextField(help_text='Type Here:')
    image_data = models.ImageField(upload_to="website/media/", null=True, blank=True, help_text='Upload Image:')
    video_data = models.FileField(null=True, upload_to="website/media/", blank=True, validators=[validate_file_extension])
    public_data = models.BooleanField(help_text='Public?', null=True)
    approval = models.BooleanField(help_text='Is this post approved?', default=True)

class PostComment(models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    post = models.ForeignKey(Post_Data, on_delete=models.CASCADE, related_name='post_comment_id')
    post_comment = models.CharField(max_length=500)
    timestamp = models.DateTimeField(auto_now_add=True)
    
    def __str__(self):
        return f"Comment by {self.user} on {self.post}"

urls.py：

urlpatterns = [
    path('', views.index, name='RoamTrip'),
]

urlpatterns += static(settings.STATIC_URL, document_root=settings.STATIC_ROOT)
urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)

结果我得到了这个错误：

TypeError：无法解压不可迭代的 NoneType 对象

Answer 1

这是错误的行：

postid = Post_Data.objects.get(pk)

.get()

接受关键字参数或 Q 对象。我猜你想按 PK 过滤，所以该行应该是：

postid = Post_Data.objects.get(pk=pk)