Question

我正在尝试查找与特定campus_id匹配的数据库。如果我使用整数，则可使用此功能，但不适用于字符串。

models.py

from django.db import models

class Campus(models.Model):
   campus_id = models.IntegerField(primary_key=True)
   name = models.CharField(max_length=100)

   def __str__(self):
      return self.name

class Restaurant(models.Model):
   restaurant_id = models.IntegerField(primary_key=True)
   name = models.CharField(max_length=100)
   location = models.CharField(max_length=100)
   campus_id = models.ForeignKey(Campus,on_delete = models.CASCADE)
   opening_hours = models.TimeField()
   closing_hours = models.TimeField()
   capacity = models.IntegerField()
   #staff = models.IntegerField()

   def __str__(self):
      return self.name

views.py

def restaurants(request):
    query = request.GET.get('search', None)
    context = {}
    if query and request.method == 'GET':
        results = Restaurant.objects.filter(campus_id=query)
        context.update({'results':results})
        return render(request, 'eatatdcu/restaurants.html', context)

restaurants.html

{% for x in results %}


        {{x.name}} , {{x.location}}

        <br>

    {% endfor %}

跟踪日志

Traceback (most recent call last):
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\core\handlers\exception.py", line 41, in inner
        response = get_response(request)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\core\handlers\base.py", line 187, in _get_response
        response = self.process_exception_by_middleware(e, request)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\core\handlers\base.py", line 185, in _get_response
        response = wrapped_callback(request, *callback_args, **callback_kwargs)
      File "C:\Users\Calvin\Desktop\CA377\2019-ca377-EatAtDCU\src\ca377\eatatdcu\views.py", line 13, in restaurants
        results = Restaurant.objects.filter(campus_id=query)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\manager.py", line 85, in manager_method
        return getattr(self.get_queryset(), name)(*args, **kwargs)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\query.py", line 781, in filter
        return self._filter_or_exclude(False, *args, **kwargs)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\query.py", line 799, in _filter_or_exclude
        clone.query.add_q(Q(*args, **kwargs))
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\sql\query.py", line 1260, in add_q
        clause, _ = self._add_q(q_object, self.used_aliases)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\sql\query.py", line 1286, in _add_q
        allow_joins=allow_joins, split_subq=split_subq,
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\sql\query.py", line 1216, in build_filter
        condition = lookup_class(lhs, value)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\lookups.py", line 24, in __init__
        self.rhs = self.get_prep_lookup()
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\fields\related_lookups.py", line 110, in get_prep_lookup
        self.rhs = target_field.get_prep_value(self.rhs)
      File "C:\Users\Calvin\AppData\Local\Programs\Python\Python36\lib\site-packages\django\db\models\fields\__init__.py", line 1849, in get_prep_value
        return int(value)
    ValueError: invalid literal for int() with base 10: 'dcu alpha'

Answer 1

我在错误消息中看到您试图在字段dcu alpha（这是一个Restaurant.campus_id中搜索值ForeignKey的原因，因此在数据库中它将具有以下类型：模型Campus的PK，它是一个整数）。 Django尝试将搜索值转换为int，因为该字段是整数。

也许您想搜索其他字段，也许：

name（Restaurant实例的名称）
还是campus_id__name（属于Campus实例的Restaurant实例的名称）？

或者您可以添加错误处理：

def restaurants(request):
    query = request.GET.get('search', None)
    context = {}
    if query and request.method == 'GET':
        try:
            query_int = int(query)
        except ValueError:
            query_int = -1

        results = Restaurant.objects.filter(campus_id=query_int)
        context.update({'results':results})
        return render(request, 'eatatdcu/restaurants.html', context)

以10为底的int（）的无效文字：“字符串”

1 个答案: