Python 如何使用基于类的视图继承来重写父类？

在我的ShowChart中有一个名为Electronic（Electronic.objects.values..etc）的模型，在我的继承类（ChartElectrical）中，它需要更改为Electronic（Electronic.objects.values..etc），这里我只传递它。我不知道怎么做

 class ShowChart(View):
   def get(self, request):
    my_count = Electrical.objects.values('allocated_time')\
        .annotate(complete=Count('allocated_time', filter=Q(batch_18=True)),
                  not_complete=Count('allocated_time', 
                   filter=Q(batch_18=False)),
                  complete_1=Count('allocated_time', 
                       filter=Q(batch_19=True)),
                  not_complete_1=Count('allocated_time', 
                  filter=Q(batch_19=False)),
                  complete_2=Count('allocated_time', 
                     filter=Q(batch_20=True)),
                  not_complete_2=Count('allocated_time', 
                   filter=Q(batch_20=False)),
                  complete_3=Count('allocated_time', 
                   filter=Q(batch_21=True)),
                  not_complete_3=Count('allocated_time', 
                filter=Q(batch_21=False)))

    c_batch_18 = list()
    n_batch_18 = list()
    c_batch_19 = list()
    n_batch_19 = list()
    c_batch_20 = list()
    n_batch_20 = list()
    c_batch_21 = list()
    n_batch_21 = list()

    for entry in my_count:
        c_batch_18.append(entry['complete'] * entry['allocated_time'])
        n_batch_18.append(entry['not_complete'] * entry['allocated_time'])
        c_batch_19.append(entry['complete_1'] * entry['allocated_time'])
        n_batch_19.append(entry['not_complete_1'] * entry['allocated_time'])
        c_batch_20.append(entry['complete_2'] * entry['allocated_time'])
        n_batch_20.append(entry['not_complete_2'] * entry['allocated_time'])
        c_batch_21.append(entry['complete_3'] * entry['allocated_time'])
        n_batch_21.append(entry['not_complete_3'] * entry['allocated_time'])

    survived_series = [sum(c_batch_18), sum(c_batch_19), sum(c_batch_20), sum(c_batch_21), 0]
    not_survived_series = [sum(n_batch_18), sum(n_batch_19), sum(n_batch_20), sum(n_batch_21), 0]

    return render(request, 'chart.html', {'survived_series': json.dumps(survived_series),
                                          'not_survived_series': json.dumps(not_survived_series)})


   class ChartElectrical(ShowChart):
    pass

---

我认为应该用另一种方法移动视图的

my_count

部分，然后在子视图中覆盖它。像这样：

class ShowChart(View):
   def get_my_count(self):
      my_count = Electrical.objects.values('allocated_time')\
        .annotate(complete=Count('allocated_time', filter=Q(batch_18=True)),
                  not_complete=Count('allocated_time', 
                   filter=Q(batch_18=False)),
                  complete_1=Count('allocated_time', 
                       filter=Q(batch_19=True)),
                  not_complete_1=Count('allocated_time', 
                  filter=Q(batch_19=False)),
                  complete_2=Count('allocated_time', 
                     filter=Q(batch_20=True)),
                  not_complete_2=Count('allocated_time', 
                   filter=Q(batch_20=False)),
                  complete_3=Count('allocated_time', 
                   filter=Q(batch_21=True)),
                  not_complete_3=Count('allocated_time', 
                filter=Q(batch_21=False)))
     return my_count

   def get(self, request):
    c_batch_18 = list()
    n_batch_18 = list()
    c_batch_19 = list()
    n_batch_19 = list()
    c_batch_20 = list()
    n_batch_20 = list()
    c_batch_21 = list()
    n_batch_21 = list()

    for entry in self.get_my_count():
        c_batch_18.append(entry['complete'] * entry['allocated_time'])
        n_batch_18.append(entry['not_complete'] * entry['allocated_time'])
        c_batch_19.append(entry['complete_1'] * entry['allocated_time'])
        n_batch_19.append(entry['not_complete_1'] * entry['allocated_time'])
        c_batch_20.append(entry['complete_2'] * entry['allocated_time'])
        n_batch_20.append(entry['not_complete_2'] * entry['allocated_time'])
        c_batch_21.append(entry['complete_3'] * entry['allocated_time'])
        n_batch_21.append(entry['not_complete_3'] * entry['allocated_time'])

    survived_series = [sum(c_batch_18), sum(c_batch_19), sum(c_batch_20), sum(c_batch_21), 0]
    not_survived_series = [sum(n_batch_18), sum(n_batch_19), sum(n_batch_20), sum(n_batch_21), 0]

    return render(request, 'chart.html', {'survived_series': json.dumps(survived_series),
                                          'not_survived_series': json.dumps(not_survived_series)})

class ChartElectrical(ShowChart):
   def get_my_count(self):
      # overriding get_my_count function
      my_count = Electrical.objects.values(...)
      return my_count

可能的优化 此外，以下是一些优化想法：

1.您可以通过注释进行

c\u batch\u 18

，

n\u batch\u 18

等计算。像这样：

class ShowChart(View):
   def get_my_count(self):
      my_count = Electrical.objects.values('allocated_time')\
        .annotate(complete=Count('allocated_time', filter=Q(batch_18=True)),
                  not_complete=Count('allocated_time', 
                   filter=Q(batch_18=False)),
                  complete_1=Count('allocated_time', 
                       filter=Q(batch_19=True)),
                  not_complete_1=Count('allocated_time', 
                  filter=Q(batch_19=False)),
                  complete_2=Count('allocated_time', 
                     filter=Q(batch_20=True)),
                  not_complete_2=Count('allocated_time', 
                   filter=Q(batch_20=False)),
                  complete_3=Count('allocated_time', 
                   filter=Q(batch_21=True)),
                  not_complete_3=Count('allocated_time', 
                filter=Q(batch_21=False)))
     return my_count

   def get(self, request):
    c_batch_18 = list()
    n_batch_18 = list()
    c_batch_19 = list()
    n_batch_19 = list()
    c_batch_20 = list()
    n_batch_20 = list()
    c_batch_21 = list()
    n_batch_21 = list()

    for entry in self.get_my_count():
        c_batch_18.append(entry['complete'] * entry['allocated_time'])
        n_batch_18.append(entry['not_complete'] * entry['allocated_time'])
        c_batch_19.append(entry['complete_1'] * entry['allocated_time'])
        n_batch_19.append(entry['not_complete_1'] * entry['allocated_time'])
        c_batch_20.append(entry['complete_2'] * entry['allocated_time'])
        n_batch_20.append(entry['not_complete_2'] * entry['allocated_time'])
        c_batch_21.append(entry['complete_3'] * entry['allocated_time'])
        n_batch_21.append(entry['not_complete_3'] * entry['allocated_time'])

    survived_series = [sum(c_batch_18), sum(c_batch_19), sum(c_batch_20), sum(c_batch_21), 0]
    not_survived_series = [sum(n_batch_18), sum(n_batch_19), sum(n_batch_20), sum(n_batch_21), 0]

    return render(request, 'chart.html', {'survived_series': json.dumps(survived_series),
                                          'not_survived_series': json.dumps(not_survived_series)})

class ChartElectrical(ShowChart):
   def get_my_count(self):
      # overriding get_my_count function
      my_count = Electrical.objects.values(...)
      return my_count

从django.db.models导入ExpressionWrapper，IntegerField
mycount=mycount.annotate（c_batch_18=ExpressionWrapper(
F（'complete'）*F（'allocated_time'），output_field=IntegerField（））
.annotate（n_batch_18=ExpressionWrapper(
F（'not_complete'）*F（'allocated_time'）、output_field=IntegerField（））#等等

2.您还可以通过聚合计算和：

从django.db.models导入总和
my_count_sums=my_count.aggregate（c_batch_18_sum=sum（'c_batch_18'）、n_batch_18=sum（'n_batch_18'））等等
生存=列表（过滤器（lambda x:x.key（）.startswith（'c_batch'），my_count_sums））
not_surved=list（过滤器（lambda x:x.key（）.startswith（'n_batch'），my_count_sums））

---

通过使用这些优化，您将通过DB完成大部分计算，而不是依赖python资源。

是的，它正在工作！非常感谢您的支持！很好，请考虑把它标记为。此外，请检查优化的想法，与此答案共享