一、购物车数据同步模块
1.定义数据同步中间件
from django.utils.deprecation import MiddlewareMixin
from carts.models import ShoppingCart
class SessionSyncMiddleware(MiddlewareMixin):
def process_response(self, request, response):
# 没有登录就不用做数据同步
# 登录情况才做数据从session同步到数据库，且重新更新session数据
user_id = request.session.get('user_id')
if user_id:
# 登录情况
session_goods = request.session.get('goods')
if session_goods:
# 1.判断session中商品是否存在于数据库中，如果存在则更新
# 2.如果不存在则创建
shop_carts = ShoppingCart.objects.filter(user_id=user_id)
# 更新购物车中的商品数量，记录更新商品的id值
data = []
for goods in shop_carts:
for se_goods in session_goods:
if se_goods[0] == goods.goods_id:
goods.nums = se_goods[1]
goods.save()
data.append(se_goods[0])
# 添加
session_goods_ids = [i[0] for i in session_goods]
add_goods_ids = list(set(session_goods_ids) - set(data))
for add_goods_id in add_goods_ids:
for session_good in session_goods:
if add_goods_id == session_good[0]:
ShoppingCart.objects.create(user_id=user_id, goods_id=add_goods_id, nums=session_good[1])
# 将数据库同步到session
new_shop_carts = ShoppingCart.objects.filter(user_id=user_id)
session_new_goods = [[i.goods_id, i.nums, i.is_select] for i in new_shop_carts]
request.session['goods'] = session_new_goods
return response
二、购物车功能模块
1.在urls.py配置文件中定义路由
from django.conf.urls import url, include
from carts import views
urlpatterns = [
# 购物车页面
url(r'^cart/', views.cart, name='cart'),
# 加入购物车
url(r'^add_cart/', views.add_cart, name='add_cart'),
# 计算购物车中的商品数量
url('^count_cart/', views.count_cart, name='count_cart'),
# 修改购物车中商品的勾选状态和商品属性
url('^change_cart/', views.change_cart, name='change_cart'),
# 删除购物车中的商品
url('^del_cart/(\d+)/', views.del_cart, name='del_cart'),
]
2.计算购物车中的商品数量
from django.http import JsonResponse
def count_cart(request):
if request.method == 'GET':
session_goods = request.session.get('goods')
count = len(session_goods) if session_goods else 0
return JsonResponse({'code': 200, 'msg': '请求成功', 'count': count})
3.修改购物车中商品的勾选状态和商品属性
from django.http import JsonResponse
def change_cart(request):
if request.method == 'POST':
# 获取前端Ajax传递的goods_id,is_select,nums
goods_id = int(request.POST.get('goods_id'))
is_select = request.POST.get('is_select')
nums = request.POST.get('nums')
# 获取session中商品的信息
session_goods = request.session.get('goods')
for goods in session_goods:
if goods_id == goods[0]:
# 修改session中的商品的数量和选择状态
goods[1] = int(nums) if nums else goods[1]
goods[2] = int(is_select) if is_select else goods[2]
request.session['goods'] = session_goods
return JsonResponse({'code': 200, 'msg': '请求成功'})
4.删除购物车中的商品
from django.http import JsonResponse, HttpResponseRedirect
from carts.models import ShoppingCart
def del_cart(request, id):
if request.method == 'GET':
user_id = request.session.get('user_id')
if user_id:
# 登录情况，删除数据库中的数据
ShoppingCart.objects.filter(user_id=user_id, goods_id=id).delete()
# 不管登录与否，删除session中的数据
session_goods = request.session.get('goods')
for goods in session_goods:
if goods[0] == int(id):
session_goods.remove(goods)
request.session['goods'] = session_goods
return HttpResponseRedirect(reverse('carts:cart'))
5.购物车页面JS代码
{% extends 'base_main.html' %}
{% block title %}
天天生鲜-购物车
{% endblock %}
{% block js %}
{% load static %}
{% endblock %}
{% block search %}
| 购物车
{% endblock %}
{% block content %}
全部商品0件
- 商品名称
- 商品单位
- 商品价格
- 数量
- 小计
- 操作
{% if goods_all %}
{% for goods in goods_all %}
- {{ goods.0.name }}
{{ goods.0.shop_price }}/500g
- 500g
- {{ goods.0.shop_price }}元
-
- {{ goods.2 }}元
- 删除
{% endfor %}
{% endif %}
- 全选
- 合计(不含运费)：¥42.60
共计2件商品
- 去结算
{% endblock %}
{% block js2 %}
{% csrf_token %}
{% endblock %}