所以我得到AttributeError at /product/7 'QuerySet' object has no attribute 'category'错误每当我访问详细信息视图页面
它说没有属性category，但我已经在models.py中与另一个称为category的模型形成了关系，我尝试使用category.id，但这不起作用
views.py
def detailview(request, id):
book = get_object_or_404(Book, pk=id)
if request.user.is_authenticated:
oof = CartItem.objects.filter(user=request.user).values_list('book', flat=True)
lmao = OrderItem.objects.filter(user=request.user).values_list('book', flat=True)
hehe = CartItem.objects.filter(user=request.user)
number = 0
for num in hehe:
number += 1
fianlprice = 0
for item in hehe:
fianlprice += item.book.price
specific = Book.objects.filter(pk=id)
matching_books = Book.objects.filter(category=specific.category).exclude(pk=id)[:3]
reviews = Paginator(ProductReview.objects.filter(book=id), 5)
review_page = request.GET.get('reviews')
review_objects = reviews.get_page(review_page)
one_two_star = ProductReview.objects.filter(book=id, rating=1).count() + ProductReview.objects.filter(book=id, rating=2).count()
three_star = ProductReview.objects.filter(book=id, rating=3).count()
four_star = ProductReview.objects.filter(book=id, rating=4).count()
five_star = ProductReview.objects.filter(book=id, rating=5).count()
checking = True
if ProductReview.objects.filter(book=id, user=request.user).exists():
checking = False
if checking == False:
gotten_review = ProductReview.objects.get(user=request.user)
params = {'book':book, 'price':fianlprice, 'cart':oof, 'order':lmao, 'number':number, 'matching_books':matching_books, 'reviews':review_objects,
'one_two_star':one_two_star, 'three_star':three_star, 'four_star':four_star, 'five_star':five_star, 'gotten_review':gotten_review, 'checking':checking}
return render(request, 'main/detail.html', params)
else:
specific = Book.objects.filter(pk=id)
matching_books = Book.objects.filter(category=specific.category).exclude(pk=id)[:3]
reviews = Paginator(ProductReview.objects.filter(book=id), 5)
review_page = request.GET.get('reviews')
review_objects = reviews.get_page(review_page)
one_two_star = ProductReview.objects.filter(book=id, rating=1).count() + ProductReview.objects.filter(book=id, rating=2).count()
three_star = ProductReview.objects.filter(book=id, rating=3).count()
four_star = ProductReview.objects.filter(book=id, rating=4).count()
five_star = ProductReview.objects.filter(book=id, rating=5).count()
params = {'book':book, 'matching_books':matching_books, 'reviews':review_objects, 'one_two_star':one_two_star, 'three_star':three_star, 'four_star':four_star, 'five_star':five_star}
return render(request, 'main/detail.html', params)
detail.html
<h1>{{ book.name }}</h1>
<img src="/media/{{ book.image }}">
<h3>{{ book.description }}</h3>
<h2>{{ book.price }}</h2>
<main>
<div class="container dark-grey-text mt-5">
<!--Grid row-->
<div class="row wow fadeIn">
<!--Grid column-->
<div class="col-md-6 mb-4">
<img src="{{book.image.url}}" class="img-fluid" alt="">
</div>
<!--Grid column-->
<!--Grid column-->
<div class="col-md-6 mb-4">
<!--Content-->
<div class="p-4">
<div class="mb-3">
<a >
<span class="badge purple mr-1" style="color:#3167EB">{{book.category.name}}</span>
</a>
<a href="">
</a>
<a href="">
</a>
</div>
<p class="lead">
<span class="mr-1">
</span>
<span>${{book.price}}</span>
</p>
<p class="lead font-weight-bold">{{book.name}}</p>
<p>{{ book.description }}</p>
{% if book.id in cart %}
<form class="d-flex justify-content-left" method="POST" action="{% url 'removefromcartfordetail' %}">
<!-- Default input -->
<button class="btn btn-primary btn-md my-0 p" type="submit" name="removeid" value="{{book.id}}" style="background-color:#FF0000;">Remove from cart <i class="fa fa-shopping-cart ml-1"></i></button>
</form>
{% elif book.id in order %}
<form class="d-flex justify-content-left" method="GET" action="{% url 'getorders' %}">
<!-- Default input -->
<button class="btn btn-primary btn-md my-0 p" type="submit" style="background-color:#FFFF00;">Item Owned <i class="fa fa-shopping-cart ml-1"></i></button>
</form>
{% else %}
<form class="d-flex justify-content-left" method="POST" action="{% url 'addtocartfordetail' %}">
<!-- Default input -->
<button class="btn btn-primary btn-md my-0 p" type="submit" name="BookID" value="{{book.id}}" style="background-color:#3167EB;">Add to cart <i class="fa fa-shopping-cart ml-1"></i></button>
</form>
{% endif %}
</div>
<!--Content-->
</div>
<!--Grid column-->
</div>
<!--Grid row-->
<hr>
<!--Grid row-->
<div class="row d-flex justify-content-center wow fadeIn">
<!--Grid column-->
<div class="col-md-6 text-center">
<h2 class="my-4 h2">Related books to {{book.category.name}}</h2>
</div>
<!--Grid column-->
</div>
<!--Grid row-->
<!--Grid row-->
<div class="row wow fadeIn">
<!--Grid column-->
{% for matching_book in matching_books %}
<div class="col-lg-4 col-md-12 mb-4 text-center" >
<img src="{{ matching_book.image.url }}" class="img-fluid" alt="">
<h2><a href="{% url 'detailview' matching_book.id %}">{{ matching_book.name }}</a> </h2>
</div>
{% endfor %}
<!--Grid column-->
<!--Grid column-->
<!--Grid column-->
<!--Grid column-->
<!--Grid column-->
</div>
<!--Grid row-->
</div>
</main>
{% if user.is_authenticated %}
{% if checking == True %}
<style> .rating {
text-align: center;
align-content: center;
}
/* :not(:checked) is a filter, so that browsers that don’t support :checked don’t
follow these rules. Every browser that supports :checked also supports :not(), so
it doesn’t make the test unnecessarily selective */
.rating:not(:checked) > input {
position:absolute;
top:-9999px;
clip:rect(0,0,0,0);
}
.hehe2 {
align-content: center;
display: flex;
justify-content: center;
}
.rating:not(:checked) > label {
float:right;
width:1em;
/* padding:0 .1em; */
overflow:hidden;
white-space:nowrap;
cursor:pointer;
font-size:300%;
/* line-height:1.2; */
color:#ddd;
}
.rating:not(:checked) > label:before {
content: '★ ';
}
.rating > input:checked ~ label {
color: dodgerblue;
}
.rating:not(:checked) > label:hover,
.rating:not(:checked) > label:hover ~ label {
color: dodgerblue;
}
.rating > input:checked + label:hover,
.rating > input:checked + label:hover ~ label,
.rating > input:checked ~ label:hover,
.rating > input:checked ~ label:hover ~ label,
.rating > label:hover ~ input:checked ~ label {
color: dodgerblue;
}
.rating > label:active {
position:relative;
top:2px;
left:2px;
}
</style>
<section >
<div class="container justify-content-center hehe2" style="align-content: center;">
<div class="row form-group ">
<form method="POST">
<div class="rating justify-content-center">
<input type="radio" id="star5" name="rating" value="5"><label for="star5" title="Great">5 stars</label>
<input type="radio" id="star4" name="rating" value="4"><label for="star4" title="Good">4 stars</label>
<input type="radio" id="star3" name="rating" value="3"><label for="star3" title="Just fine">3 stars</label>
<input type="radio" id="star2" name="rating" value="2"><label for="star2" title="Bad">2 stars</label>
<input type="radio" id="star1" name="rating" value="1"><label for="star1" title="Very Bad">1 star</label>
</div>
<input type="text" name="name" class="form-control" id="exampleFormControlInput1" placeholder="Your name">
<br>
<input type="text" name="title" class="form-control" id="exampleFormControlInput1" placeholder="Title">
<br>
<textarea name="description" maxlength="500" class="form-control" id="exampleFormControlTextarea1" rows="3" placeholder="Description"></textarea>
<br>
<button type="submit" value="{{ book.id }}" name="BookID" class="btn btn-primary" style="background-color:#3167EB;">Post review</button>
</form>
</div>
</div>
</section>
{% else %}
<section >
<div class="container hehe2" style="align-content: center;">
<h1> Your review: </h1>
<br>
</div>
<div class="container hehe2">
<h1>
{% if gotten_review.rating == 1 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
{% elif gotten_review.rating == 2 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
{% elif gotten_review.rating == 3 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
{% elif gotten_review.rating == 4 %}
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
{% elif gotten_review.rating == 5 %}
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
{% endif %}
</h1>
</div>
<div class="container hehe2">
<h1> <strong>{{gotten_review.title}}</strong>
</h1>
</div>
<div class="container hehe2 pb-5">
<h3>{{gotten_review.description}} </h3>
</div>
</section>
{% endif %}
{% else %}
{% endif %}
<div class="container text-center">
<h1 style="color:#3167EB"> 5-Star reviews : {{five_star}} </h1>
<h1 style="color:#00FF00"> 4-Star reviews : {{four_star}} </h1>
<h1 style="color:#FFFF00"> 3-Star reviews : {{three_star}} </h1>
<h1 style="color:#FF0000"> 1-2 Star reviews : {{one_two_star}} </h1>
<h1 class="pt-5 pb-5"> Latest Reviews </h1>
</div>
{% if reviews %}
{% if reviews.has_other_pages %}
{% for review in reviews %}
<div class="container">
<h2> {{ review.name }} </h2>
{% if review.rating == 1 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
{% elif review.rating == 2 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
{% elif review.rating == 3 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
{% elif review.rating == 4 %}
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
{% elif review.rating == 5 %}
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
{% endif %}
<h3> {{ review.title }} </h3>
<p> {{ review.description }} </p>
</div>
{% endfor %}
{% if reviews.has_previous %}
<li class="page-item">
<a class="page-link" href="?reviews={{reviews.previous_page_number}}" aria-label="Previous" style="color:#3167EB;">
<span aria-hidden="true">«</span>
<span class="sr-only">Previous</span>
</a>
</li>
{% else %}
<li class="page-item">
<a class="page-link disabled" aria-label="Previous" >
<span aria-hidden="true">«</span>
<span class="sr-only">Previous</span>
</a>
</li>
{% endif %}
{% for i in reviews.page_range %}
{% if reviews.number == i %}
<li class="page-item active"><a class="page-link">{{i}}</a></li>
{% else %}
<li class="page-item"><a class="page-link" href="?reviews={{i}}">{{i}}</a></li>
{% endif %}
{% endfor %}
{% if reviews.has_next %}
<li class="page-item">
<a class="page-link" href="?reviews={{reviews.next_page_number}}" aria-label="Next" style="color:#3167EB;">
<span aria-hidden="true">»</span>
<span class="sr-only">Next</span>
</a>
</li>
{% else %}
<li class="page-item disabled">
<a class="page-link" aria-label="Next">
<span aria-hidden="true">»</span>
<span class="sr-only">Next</span>
</a>
</li>
{% endif %}
{% else %}
{% for review in reviews %}
<div class="container">
<h2> {{ review.name }} </h2>
{% if review.rating == 1 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
{% elif review.rating == 2 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FF0000"></i>
{% elif review.rating == 3 %}
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#FFFF00"></i>
{% elif review.rating == 4 %}
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#00FF00"></i>
{% elif review.rating == 5 %}
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
<i class="fa fa-star" aria-hidden="true" style="color:#3167EB"></i>
{% endif %}
<h3> {{ review.title }} </h3>
<p> {{ review.description }} </p>
</div>
{% endfor %}
{% endif %}
{% else %}
<h1>There are currently no reviews for this product!</h1>
{% endif %}
正如评论中所解释的，您正在做一个过滤器，它返回一个查询集，而不是模型的单个实例。
并且假设您的过滤器位于具有给定ID的主键上，那么您可以安全地使用它执行get，只要您捕获未发现的异常。这样，您将获得一个实例，并能够使用它执行.category。
因此你应该这样做;
try:
specific_book = Book.objects.get(pk=id)
matching_books = Book.objects.filter(category=specific_book.category).exclude(pk=id)[:3]
except Book.DoesNotExist:
# No book found
raise