Question

您好我正在处理我的电子商务django教程，由于某些原因，我的简单购物车计数无效。每次我添加到购物车时，我的cart.html中的{{cart_item_count}}都是0

另外关于这段代码，这本书的carts.py为cart.py，但由于某些原因应用程序是购物车，因此我不能重命名我的cart.py“carts.py”并做了这个从购物车进口购物车作为购物车

Django不允许py文件与app同名吗???

帮助代码

carts.py有一个函数def cart_disinct_item_count（request），它返回我在views.py中调用的计数，用于设置变量“cart_item_count”，该变量显示在我的cart.html页面中但当前无论我的表单是什么返回0。

我没有发布整个项目代码，但我认为我得到了所需的所有相关信息。

由于

cart.html

{% block content %}
<h1>Cart Page Here</h1>
Cart item count: {{cart_item_count }}
{% endblock %}

购物车views.py

# Create your views here.
from django.shortcuts import render_to_response
from django.template import RequestContext
from cart import carts as cart

def show_cart(request, template_name="cart/cart.html"):
    cart_item_count = cart.cart_disinct_item_count(request)
    page_title = 'Shopping Cart'
    return render_to_response("cart/cart.html", locals(),
                          context_instance = RequestContext(request))

购物车商品型号

class CartItem(models.Model):
cart_id = models.CharField(max_length=50)
date_added = models.DateTimeField(auto_now_add = True)
quantity = models.IntegerField(default = 1)
product = models.ForeignKey('catalog.Product', unique = False)

class Meta:
    app_label = ''
    db_table = 'cart_items'
    ordering = ['date_added']

def total(self):
    return self.quantity * self.product.price
def name(self):
    return self.product.name
def price(self):
    return self.product.price

def get_absolute_url(self):
    return self.product.get_absolute_url()
def augment_quantity(self, quantity):
        """ called when a POST request comes in for a Product instance already in the shopping cart """
        self.quantity = self.quantity + int(quantity)
        self.save()

carts.py

def get_cart_items(request):
    return CartItem.objects.filter(cart_id=_cart_id(request))

#add an item to the cart
def add_to_cart(request):    
    postdata = request.POST.copy()
    #get product slug from post data, return blank if empty
    product_slug = postdata.get('product_slug', '')
    #get quantity added, return 1 if empty
    quantity = postdata.get('quantity', 1)
    #fetch the product or return a missing page error
    p = get_object_or_404(Product, slug = product_slug)
    #get products in cart
    cart_products = get_cart_items(request)
    product_in_cart = False
    #check to see if item is already in cart
    for cart_item in cart_products:
        if cart_item.product.id == p.id:
            #update the quantity if found
            cart_item.augment_quantity(quantity)
            product_in_cart = True
        if not product_in_cart:
            #create and save a new cart item
            ci = CartItem()
            ci.product = p
            ci.quantity = quantity
            ci.cart_id = _cart_id(request)
            ci.save()
#returns the total number of items in the user's cart
def cart_disinct_item_count(request):
    return get_cart_items(request).count()

forms.py：

class ProductAddToCartForm(forms.Form):
quantity = forms.IntegerField(widget=forms.TextInput(attrs={'size':'2',
                              'value':'1', 'class':'quantity'}),
                              error_messages={'invalid': 'Please enter a valid quantity'},
                              min_value = 1)
product_slug = forms.CharField(widget = forms.HiddenInput())

#override the default __init__ so we can set the request
def __init__(self, request = None, *args, **kwargs):
    self.request = request
    super(ProductAddToCartForm, self).__init__(*args, **kwargs)

*的修改 ** 忘了添加显示产品的视图并调用add_to_cart：

#new product view, with POST vs GET detection

def show_product（request，product_slug，template_name =“catalog / product.html”）：

p = get_object_or_404(Product, slug=product_slug)

categories = p.categories.all()
page_title = p.name
meta_keywords = p.meta_keywords
meta_description = p.meta_description
#need to evaluate the HTTP method
if request.method == 'POST':

    #add to cart....create the bound form
    postdata = request.POST.copy()
    form = ProductAddToCartForm(request, postdata)

    #check if posted data is valid
    if form.is_valid():
        #add to cart and redirect to cart page
        cart.add_to_cart(request)
        # if test cookie worked, get rid of it
        if request.session.test_cookie_worked():
            request.session.delete_test_cookie()

        url = urlresolvers.reverse('show_cart')
        return HttpResponseRedirect(url)
else:
    # it's a GET, create the unbound form. Note request as a kwarg
    form = ProductAddToCartForm(request = request, label_suffix = ':')


    #assign the hidden input the product slug
    form.fields['product_slug'].widget.attrs['value'] = product_slug
    #set the test cookie on our first GET request
    request.session.set_test_cookie()

    return render_to_response("catalog/product.html", locals(),   context_instance=RequestContext(request))

Answer 1

发现错误:)缩进问题（愚蠢的python）j / k第一个是我的，第二个是正确的。得好用这个。很容易忽视未经训练的眼睛......

def add_to_cart(request):    
postdata = request.POST.copy()
product_slug = postdata.get('product_slug', '')
quantity = postdata.get('quantity', 1)
p = get_object_or_404(Product, slug = product_slug)
cart_products = get_cart_items(request)
product_in_cart = False
for cart_item in cart_products:
    if cart_item.product.id == p.id:
        cart_item.augment_quantity(quantity)
        product_in_cart = True
    if not product_in_cart:
        ci =  CartItem()
        ci.product = p
        ci.quantity = quantity
        ci.cart_id = _cart_id(request)
        ci.save()

以下是书籍并且有效：

def add_to_cart(request):
postdata = request.POST.copy()
product_slug = postdata.get('product_slug','')
quantity = postdata.get('quantity',1)
p = get_object_or_404(Product, slug=product_slug)
cart_products = get_cart_items(request)
product_in_cart = False
for cart_item in cart_products:
    if cart_item.product.id == p.id:
        cart_item.augment_quantity(quantity)
        product_in_cart = True
if not product_in_cart:
    ci = CartItem()
    ci.product = p
    ci.quantity = quantity
    ci.cart_id = _cart_id(request)
    ci.save()

Django购物车没有更新数量

1 个答案: