Django错误：“视图auctions.views.new_bid没有返回HttpResponse对象，而是返回了None。”

Question

我得到的错误是：“视图auctions.views.new_bid没有返回HttpResponse对象，而是返回了None。”

有人知道它为什么返回None吗？任何帮助都是非常感谢的。

此视图将允许用户对网站上的项目进行竞价，类似于ebay。new_bid允许他们出价，而listingpage显示的是实际项目的页面。列表页面加载正常，当我在竞价表单中输入一个数字并保存时，我只是得到了错误。在站点的/admin部分，我可以看到号码没有保存。

views.py：

    def new_bid(request, listingid):
        if request.method == 'POST':
            auction_to_add = Listings.objects.get(id=listingid)
            total_bid = request.POST.get("total_bid")
            bid = Bid.objects.create(user=request.user, listingid=auction_to_add, bid=total_bid)
            auction_to_add.bids.add(bid)
            auction_to_add.last_bid = bid
            auction_to_add.save()
            return HttpResponse('success')
           


    def listingpage(request, listingid):
        comments = Comments.objects.filter(listingid=listingid)
        item = Listings.objects.get(id=listingid)
        return render(request, "auctions/listing.html", {
            "listingid": listingid,
            "comments": comments,
            "product": item,
        })

列表页面的html的一部分，允许用户出价：

<form id="addBid" data-startingbid="{{product.starting_bid}}" data-lastbid=" 
  {{product.last_bid.bid}}" data-auction="{{product.id}}" action="{% url 'new_bid' 
product.id %}">
                {% csrf_token %}
                <input type="number" name="totalBid" id="newBid" placeholder="Total bid">
                    <button class="button-auction" type="submit">Send</button>
</form>

urls.py

urlpatterns = [

    path("listings/<int:listingid>", views.listingpage, name="listingpage"),
    path("new_bid/<int:listingid>", views.new_bid, name="new_bid"),
]

models.py

class Bid(models.Model):
    user = models.CharField(max_length=64)
    title = models.CharField(max_length=64)
    bid = models.IntegerField(blank=True, null=True)
    listingid = models.ForeignKey('Listings', on_delete=models.CASCADE, 
    related_name='listing_for_bid')


class Listings(models.Model):

    title = models.CharField(max_length=64)
    description = models.TextField(max_length=250)
    starting_bid = models.IntegerField()
    bids = models.ManyToManyField('Bid', related_name='bids_in_the_auction', blank=True)
    last_bid = models.ForeignKey('Bid', on_delete=models.CASCADE, 
    related_name='last_bid_for_the_auction', blank=True,
                             null=True)

Answer 1

当请求方法不是POST时，您的new_bid(request, listingid)函数不返回任何内容(因此返回None)。

现在，您没有在表单中指定方法，因此它缺省为GET。以下更改应该可以做到这一点：

<form id="addBid" data-startingbid="{{product.starting_bid}}" data-lastbid=" 
  {{product.last_bid.bid}}" data-auction="{{product.id}}" action="{% url 'new_bid' 
product.id %}" method="POST">
                {% csrf_token %}
                <input type="number" name="totalBid" id="newBid" placeholder="Total bid">
                    <button class="button-auction" type="submit">Send</button>
</form>