重写ModelAdmin的 get_search_results 方法以使用所需的查询。您可以在为自动补全字段提供数据的视图的 get_queryset 方法中看到，该方法用于获取查询集-此答案的源是 https://github.com/django/django/blob/03dbdfd9bbbbd0b0172aad648c6bbe3f39541137/django/contrib/admin/views/autocomplete.py#L42 。

如果对'self‘上的 ManyToManyField 使用 autocomplete_fields ，则此示例将排除当前对象。

通过重写 get_form 获取当前对象的id

field_for_autocomplete = None
def get_form(self, request, obj=None, **kwargs):
    if obj:
        self.field_for_autocomplete = obj.pk
    return super(MyAdmin, self).get_form(request, obj, **kwargs)

接下来，覆盖 get_search_results 。仅为模型的自动完成URI修改查询集：

def get_search_results(self, request, queryset, search_term):
    queryset, use_distinct = super().get_search_results(request, queryset, search_term)
    # Exclude only for autocomplete
    if request.path == '/admin/myapp/mymodel/autocomplete/':
        queryset = queryset.exclude(field=self.field_for_autocomplete)
    return queryset, use_distinct

不知何故，我遇到了同样的问题，当我使用autocomplete_fields时，limit_choices_to没有生效，然后我为我的情况找到了一个解决方案，可能也会对其他人有帮助。这是我的一个想法和解决方案，任何人都应该为他/她的使用而更改代码。

假设我们有两个模型model_A和modle_B:我们将覆盖"get_search_results“

model_A的模型管理(因为model_B有一个foreign_key(或m2m) )，在我的例子中，我只想将选择限制到所有model_A对象，这些对象

当前没有model_B连接的对象，或者在将model_B对象更新为仅前一个model_A对象的情况下。所以我们就去

# moodels.py
class model_A(models.Model):
    name = models.CharField()
class model_B(models.Model):
    name = models.CharField()
    fk_field = models.OneToOneField( #ManyToManyField or ForeignKey
    model_A,
    related_name='fk_reverse',
    on_delete=models.CASCADE)
# admin.py
class model_A_Admin(admin.ModelAdmin):
   search_fields = ('name', )
 def get_search_results(self, request, queryset, search_term):
        import re
        queryset, use_distinct = super().get_search_results(request, queryset, search_term)
    # note: str(request.META.get('HTTP_REFERER')) is the url from which the request had come/previous url.
        if "model_b/add/" in str(request.META.get('HTTP_REFERER')):
        # if we were in creating new model_B instanse page
        # note: the url is somehow containing model_Bs calss name then / then "add"
        # so there is no related object(of model_A) for non exsisting object(of model_B)
            queryset = self.model.objects.filter(fk_reverse=None)
        elif re.search(r"model_b/\d/change/", str(request.META.get('HTTP_REFERER'))):