Question

我正在尝试按列表过滤查询集我通过

将unicode数据转换为1,4,5,6的格式

category = request.GET.getlist(category')
print type(category)



data = Leads.objects.filter(item_required__id= category )

然后我收到错误

invalid literal for int() with base 10: '1,4'

那么我该如何解决这个问题。

Traceback:
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/core/handlers/base.py" in get_response
  132.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/views/decorators/csrf.py" in wrapped_view
  58.         return view_func(*args, **kwargs)
File "/home/cp/Documents/myshopup/markatix/customapi/vendors.py" in CustomerRequirements
  365.      cust_leads = CustomerLeads.objects.filter(item_required__id__in= category ).values('customer_name','budget','event','posting_date','quantity','other','fb_id','image','title').order_by('-posting_date')
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/manager.py" in manager_method
  127.                 return getattr(self.get_queryset(), name)(*args, **kwargs)
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/query.py" in filter
  679.         return self._filter_or_exclude(False, *args, **kwargs)
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/query.py" in _filter_or_exclude
  697.             clone.query.add_q(Q(*args, **kwargs))
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/sql/query.py" in add_q
  1310.         clause, require_inner = self._add_q(where_part, self.used_aliases)
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/sql/query.py" in _add_q
  1338.                     allow_joins=allow_joins, split_subq=split_subq,
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/sql/query.py" in build_filter
  1209.             condition = self.build_lookup(lookups, col, value)
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/sql/query.py" in build_lookup
  1102.                 return final_lookup(lhs, rhs)
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/lookups.py" in __init__
  105.         self.rhs = self.get_prep_lookup()
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/lookups.py" in get_prep_lookup
  143.         return self.lhs.output_field.get_prep_lookup(self.lookup_name, self.rhs)
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/fields/__init__.py" in get_prep_lookup
  729.             return [self.get_prep_value(v) for v in value]
File "/home/cp/Documents/envMyShopUp/local/lib/python2.7/site-packages/django/db/models/fields/__init__.py" in get_prep_value
  985.         return int(value)

Exception Type: ValueError at /customapi/vendor/customer-requirements/
Exception Value: invalid literal for int() with base 10: '1,4'

提前致谢。

Answer 1

我做错了一些步骤。最后我找到了解决方案。

    category = request.GET.get('category')
l1=[]
    category_list =category.split(',')
    for i in category_list:
        a =int(i)
        l1.append(a)

cust_leads = CustomerLeads.objects.filter(item_required__id__in= l1 )

Answer 2

您还可以使用QueryDict.getlist解析请求的查询参数列表：

from django.http.request import QueryDict

query = QueryDict('category=1&category=2')
categories = query.getlist('category')  # -> ['1', '2']
leads = Leads.objects.filter(item_required__id__in=categories)

这样，用户可以通过逐个添加到查询中来为您提供类别列表。这个解决方案对你来说可能已经足够了。

但，您的用户（或您）可能希望提供免费的样式列表，并且它们可能在您的查询中有多个。在这种情况下，您必须获取所有列表，可以是主键列表，并将它们映射到可以在Django过滤器中使用的平面列表...

from itertools import chain
from django.http.request import QueryDict

query = QueryDict('categories=1,2,3&categories=4,5')
categories_strings = query.getlist('categories')  # -> ['1,2,3', '4,5']
categories = list(chain.from_iterable(
    map(lambda categories: categories.split(','), categories_strings))
)  # -> ['1', '2', '3', '4', '5']
leads = Leads.objects.filter(item_required__id__in=categories)

幸运的是，对于我们来说，你可以很容易地把它写成一个整洁的小函数：

# Your myapp/utils.py module
from itertools import chain

# Python 3.5+ type type annotated function, you can use
# this without the type annotations in Python 2.7 as well
def get_query_list(querydict: QueryDict, key: str) -> list:
    return list(chain.from_iterable(
        map(lambda query: query.split(','), querydict.getlist(key)))
    )

这就是它的工作原理：

from django.http.request import QueryDict
from myapp.utils import get_query_list

q = QueryDict('a=1&a=2&a=3,4')
get_query_list(q, 'a')  # -> ['1', '2', '3', '4']

您可以在视图中使用它：

# Your myapp/views.py module
from myapp.utils import get_query_list

def my_view(request):
    categories = get_query_list(request.GET, 'categories')  # or 'category'
    # ...

这是一种更冗长的方式，而不是使用单一查询参数代替列表，并支持多种不同的格式。

根据需要添加类型分类：

def my_view(request):
    # A nice and neat one-liner
    categories = get_query_list(request.GET, 'categories')  # or 'category'
    for item in categories:
        try:
            assert int(item)
        except ValueError:
            raise ValidationError('{} is not of correct type {}'.format(item, int))
    # Everything should be parsed and validated
    leads = Leads.objects.filter(item_required__id__in=categories)

在实施搜索或通用过滤器时，Django经常需要这种方法。

如何在django中按列表过滤

2 个答案: