无法在电子商务应用程序-django中获取产品id

Question

视图.py

from django.shortcuts import render,redirect
from .models import Cart
from new_app.models import Product
def cart_home(request):

cart_obj,new_obj=Cart.objects.new_or_get(request)
products=Cart.objects.all()
return render(request,'carts/home.html',{})


def cart_update(request):
print(request.POST)
product_id=1
print('id below')
print(product_id) // not able to get the value of product id in console
product_obj=Product.objects.get(id=product_id)
cart_obj,new_obj=Cart.objects.new_or_get(request)
if product_obj in cart_obj.products.all():
cart_obj.products.remove(product_obj)
else:
cart_obj.products.add(product_obj)
return redirect('home')

型号.py(推车(

from django.db import models
from django.conf import settings
from new_app.models import Product
from django.db.models.signals import pre_save,post_save,m2m_changed



User=settings.AUTH_USER_MODEL

class CartManager(models.Manager):
def new_or_get(self,request):
cart_id=request.session.get("cart_id",None)
# qs=self.get_queryset().filter(id=cart_id)
qs=self.get_queryset().only('products')

print(qs)
if qs.count()==1:
new_obj=False
cart_obj=qs.first()
print('cart obj below')
print(cart_obj)
if request.user.is_authenticated and cart_obj.user is None:

cart_obj.user=request.user
cart_obj.save()


else:
cart_obj=Cart.objects.new_cart(user=request.user)
new_obj=True
request.session['cart_id']=cart_obj.id
return cart_obj,new_obj

def new_cart(self,user=None):
user_obj=None
if user is not None:
if user.is_authenticated:
user_obj=user
return self.model.objects.create(user=user_obj)

class Cart(models.Model):
user=models.ForeignKey(User,null=True,blank=True,on_delete=models.CASCADE)
products=models.ManyToManyField(Product,blank=True)
subtotal=models.DecimalField(default=0.00,max_digits=100,decimal_places=2)

total=models.DecimalField(default=0.00,max_digits=100,decimal_places=2)
timestamp=models.DateTimeField(auto_now_add=True)
updated=models.DateTimeField(auto_now=True)

objects=CartManager()

def __str__(self):
return str(self.id)


def m2m_changed_cart_receiver(sender,instance,action,*args,**kwargs):
print(action)
if action=='post_add' or action=='post_remove' or action=='clear':
products=instance.products.all()
total=0
for x in products:
total += x.price
if instance.subtotal != total:
instance.subtotal=total
instance.save()
m2m_changed.connect(m2m_changed_cart_receiver,sender=Cart.products.through)


def pre_save_cart_receiver(sender,instance,*args,**kwargs):
if instance.subtotal>0:
instance.total=instance.subtotal + 10
else:
instance.total=0.00

pre_save.connect(pre_save_cart_receiver,sender=Cart)

update_cart.html

<form method='POST' action='{% url 'update' %}' class="form ">{% csrf_token %}
<input type="hidden"  name='product_id' value= "{{ product_id }}">
{% if product in cart.products.all %}
<button type="submit" class="btn btn-link">remove</button>
{% else %}
<button type="submit" class="btn btn-success">add to cart</button>
{% endif %}
</form>

终端输出：

<QueryDict: {'csrfmiddlewaretoken': ['FMk2gTq6XXxZ2HU40I6h4b3WtPl59Drf1urwUNufDZUeSFPMzGNwU4L1QuGCiCbB'], 'product_id':
['']}>     -------- GETTING EMPTY DICTIONARY  INSTEAD OF GETTING PRODUCT ID i.e. 1
id below
1
<QuerySet [<Cart: 13>]>

所以，除了csrf之外，我无法在那里获取产品id。。。。我试着单独打印产品id，它是1…(在输出中写在"下面的id"下(

1. 我在电子商务网站的CART组件上工作时遇到了一个错误。问题是product_id(与product模型有外键关系(没有从views.py文件(在cart中(中获取。我已导入PRODUCT型号。但是，当我试图打印product_id时，我得到了一个空字典
2. 正如你所看到的，我已经复制了终端的输出，csrf令牌，有一个product_id的字典，它是空的。没有显示任何值。3.如果我从product应用程序的views.py中打印产品id，就会打印它。4.产品正在添加到购物车中，正如我在管理员中检查的那样

Answer 1

您是否检查了生成的HTML中隐藏输入的值中是否存在产品id？

如果不是这样，并且我看到您使用的是product对象，那么您可能应该在模板中使用{{ product.id }}而不是{{ product_id }}(在第二行<input type="hidden" name='product_id' value= "{{ product_id }}">中(。

Answer 2

这样更新代码：

def cart_update(request, **kwargs):
product_obj=Product.objects.get(id=kwargs.get('product_id'))
cart_obj,new_obj=Cart.objects.new_or_get(request)
if product_obj in cart_obj.products.all():
cart_obj.products.remove(product_obj)
else:
cart_obj.products.add(product_obj)
return redirect('home')

并更新你的urls.py类：

url(r'^add-to-cart/(?P<product_id>[-w]+)/$', cart_update, name="cart_update"),

现在更新update_cart.html，如：

<form method='POST' action='{% url 'update' %}' class="form ">{% csrf_token %}
{% if product in cart.products.all %}
<button type="submit" class="btn btn-link">remove</button>
{% else %}
<button type="submit" class="btn btn-success">add to cart</button>
{% endif %}
</form>