如何修复此错误？字段“id”需要一个数字，但得到了“aapl”

Question

我正在尝试创建一个股票博客页面，现在在这个项目中，我在url方面遇到了问题，因为我想做的是，对于以每个股票名称创建的每个帖子，我想在该页面中显示帖子，我的解释可能有点混乱，但下面是代码和错误，您可以看到

错误

Traceback (most recent call last):
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\core\handlers\exception.py", line 34, in inner
    response = get_response(request)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\core\handlers\base.py", line 115, in _get_response
    response = self.process_exception_by_middleware(e, request)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\core\handlers\base.py", line 113, in _get_response
    response = wrapped_callback(request, *callback_args, **callback_kwargs)
  File "C:\Users\snin2\Desktop\basura\lapagina\app1\views.py", line 59, in StockView
    stock_posts = Post.objects.filter(stock=sym.lower())
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\manager.py", line 82, in manager_method
    return getattr(self.get_queryset(), name)(*args, **kwargs)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\query.py", line 904, in filter
    return self._filter_or_exclude(False, *args, **kwargs)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\query.py", line 923, in _filter_or_exclude
    clone.query.add_q(Q(*args, **kwargs))
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1350, in add_q
    clause, _ = self._add_q(q_object, self.used_aliases)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1377, in _add_q
    child_clause, needed_inner = self.build_filter(
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1311, in build_filter
    condition = self.build_lookup(lookups, col, value)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\sql\query.py", line 1165, in build_lookup
    lookup = lookup_class(lhs, rhs)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\lookups.py", line 22, in __init__
    self.rhs = self.get_prep_lookup()
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\fields\related_lookups.py", line 115, in get_prep_lookup
    self.rhs = target_field.get_prep_value(self.rhs)
  File "C:\Users\snin2\anaconda3\envs\MyDjangoEnv\lib\site-packages\django\db\models\fields\__init__.py", line 1774, in get_prep_value
    raise e.__class__(
ValueError: Field 'id' expected a number but got 'aapl'.

url.py（我将只显示相关的一个）

from django.urls import path
from app1 import views
from .views import PostView, ArticleDetailView, AddPostView, UpdatePostView, DeletePostView, AddCategoryView, CategoryView, LikeView, MyPostsView, AddCommentView, UpdateCommentView, DeleteCommentView

app_name = 'app1'

urlpatterns = [
    
    path('stock/<str:sym>/', views.StockView, name = 'stock'),
]

views.py

def StockView(request, sym):
    stock_posts = Post.objects.filter(stock=sym.lower())
    return render(request, 'app1/stockview.html', {'stock':stock_posts})

models.py

class StockNames(models.Model):
    name = models.CharField(max_length=255)
    symbol = models.CharField(max_length=255)

    def __str__(self):
        return self.symbol
        
    

class Post(models.Model):
    title = models.CharField(max_length= 255)
    header_image = models.ImageField(null = True, blank = True, upload_to = 'images/')
    author = models.ForeignKey(User, on_delete=models.CASCADE)
    body = RichTextField(blank = True, null = True)
    #body = models.TextField()
    post_date = models.DateField(auto_now_add=True)
    category = models.CharField(max_length=255, default='coding')
    snippet = models.CharField(max_length=255)
    likes = models.ManyToManyField(User, related_name = 'blog_posts')
    stock = models.ForeignKey(StockNames, null=True, on_delete=models.CASCADE)

    def total_likes(self):
        return self.likes.count()

    def __str__(self):
        return self.title + ' | ' + str(self.author)
    
    def get_absolute_url(self):
        return reverse('app1:article-detail', args=(self.id,))

Answer 1

要使用symbol过滤Post，您需要跨越查找如下所示：

stock_posts = Post.objects.filter(stock__symbol=sym.lower())