除了S.Lott的回答和评论中提到的becomingGuru，还可以通过覆盖ModelForm来添加查询集过滤器。__init__函数。(这可以很容易地应用于常规表单)它可以帮助重用并保持视图函数的整洁。

class ClientForm(forms.ModelForm):
    def __init__(self,company,*args,**kwargs):
        super (ClientForm,self ).__init__(*args,**kwargs) # populates the post
        self.fields['rate'].queryset = Rate.objects.filter(company=company)
        self.fields['client'].queryset = Client.objects.filter(company=company)

    class Meta:
        model = Client

def addclient(request, company_id):
        the_company = get_object_or_404(Company, id=company_id)

        if request.POST:
            form = ClientForm(the_company,request.POST)  #<-- Note the extra arg
            if form.is_valid():
                form.save()
                return HttpResponseRedirect(the_company.get_clients_url())
        else:
            form = ClientForm(the_company)

        return render_to_response('addclient.html', 
                                  {'form': form, 'the_company':the_company})

这对于重用很有用，比如如果在许多模型上需要通用的过滤器(通常我声明一个抽象的Form类)。如。

class UberClientForm(ClientForm):
    class Meta:
        model = UberClient

def view(request):
    ...
    form = UberClientForm(company)
    ...

#or even extend the existing custom init
class PITAClient(ClientForm):
    def __init__(company, *args, **args):
        super (PITAClient,self ).__init__(company,*args,**kwargs)
        self.fields['support_staff'].queryset = User.objects.exclude(user='michael')

除此之外，我只是在重申Django博客材料，那里有很多好的材料。

除了S.Lott的回答和评论中提到的becomingGuru，还可以通过覆盖ModelForm来添加查询集过滤器。__init__函数。(这可以很容易地应用于常规表单)它可以帮助重用并保持视图函数的整洁。

class ClientForm(forms.ModelForm):
    def __init__(self,company,*args,**kwargs):
        super (ClientForm,self ).__init__(*args,**kwargs) # populates the post
        self.fields['rate'].queryset = Rate.objects.filter(company=company)
        self.fields['client'].queryset = Client.objects.filter(company=company)

    class Meta:
        model = Client

def addclient(request, company_id):
        the_company = get_object_or_404(Company, id=company_id)

        if request.POST:
            form = ClientForm(the_company,request.POST)  #<-- Note the extra arg
            if form.is_valid():
                form.save()
                return HttpResponseRedirect(the_company.get_clients_url())
        else:
            form = ClientForm(the_company)

        return render_to_response('addclient.html', 
                                  {'form': form, 'the_company':the_company})

这对于重用很有用，比如如果在许多模型上需要通用的过滤器(通常我声明一个抽象的Form类)。如。

class UberClientForm(ClientForm):
    class Meta:
        model = UberClient

def view(request):
    ...
    form = UberClientForm(company)
    ...

#or even extend the existing custom init
class PITAClient(ClientForm):
    def __init__(company, *args, **args):
        super (PITAClient,self ).__init__(company,*args,**kwargs)
        self.fields['support_staff'].queryset = User.objects.exclude(user='michael')

除此之外，我只是在重申Django博客材料，那里有很多好的材料。

更公开的方法是在Admin类中调用get_form。它也适用于非数据库字段。例如，在这里我有一个名为'_terminal_list'的字段，可以在特殊情况下使用，从get_list(请求)中选择几个终端项，然后根据request.user进行过滤:

class ChangeKeyValueForm(forms.ModelForm):  
    _terminal_list = forms.ModelMultipleChoiceField( 
queryset=Terminal.objects.all() )

    class Meta:
        model = ChangeKeyValue
        fields = ['_terminal_list', 'param_path', 'param_value', 'scheduled_time',  ] 

class ChangeKeyValueAdmin(admin.ModelAdmin):
    form = ChangeKeyValueForm
    list_display = ('terminal','task_list', 'plugin','last_update_time')
    list_per_page =16

    def get_form(self, request, obj = None, **kwargs):
        form = super(ChangeKeyValueAdmin, self).get_form(request, **kwargs)
        qs, filterargs = Terminal.get_list(request)
        form.base_fields['_terminal_list'].queryset = qs
        return form

在运行时(例如在CreateView中)限制ModelForm的ForeignKey字段的选择的一个好方法是通过覆盖视图中的get_form_class()来为base_fields['field_name']设置limit_choices_to。

例如，在创建客户端时，将费率的选择限制为URL中标识的公司:

class ClientCreateView(LoginRequired, CreateView):
    model = Client
    fields = '__all__'
    
    def get_form_class(self):
        modelform = super().get_form_class()
        modelform.base_fields['rate'].limit_choices_to = {'company': self.kwargs['company']}
        return modelform

如果你还没有创建表单，想要更改查询集，你可以这样做:

formmodel.base_fields['myfield'].queryset = MyModel.objects.filter(...)

这在使用通用视图时非常有用!

这很简单，适用于Django 1.4:

class ClientAdminForm(forms.ModelForm):
    def __init__(self, *args, **kwargs):
        super(ClientAdminForm, self).__init__(*args, **kwargs)
        # access object through self.instance...
        self.fields['base_rate'].queryset = Rate.objects.filter(company=self.instance.company)

class ClientAdmin(admin.ModelAdmin):
    form = ClientAdminForm
    ....

你不需要在表单类中指定这个，但可以直接在ModelAdmin中执行，因为Django已经在ModelAdmin中包含了这个内置方法(来自文档):

ModelAdmin.formfield_for_foreignkey(self, db_field, request, **kwargs)¶
'''The formfield_for_foreignkey method on a ModelAdmin allows you to 
   override the default formfield for a foreign keys field. For example, 
   to return a subset of objects for this foreign key field based on the
   user:'''

class MyModelAdmin(admin.ModelAdmin):
    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if db_field.name == "car":
            kwargs["queryset"] = Car.objects.filter(owner=request.user)
        return super(MyModelAdmin, self).formfield_for_foreignkey(db_field, request, **kwargs)

一种更好的实现方法(例如创建用户可以访问的前端管理界面)是将ModelAdmin子类化，然后修改下面的方法。最终的结果是用户界面只显示与他们相关的内容，同时允许你(超级用户)看到一切。

我重写了四个方法，前两个方法使用户无法删除任何东西，它还从管理站点删除按钮。

第三个覆盖过滤任何包含引用的查询(在示例“user”或“porcupine”中(仅作为示例)。

最后一个覆盖过滤模型中的任何外键字段，以过滤与基本查询集相同的可用选项。

通过这种方式，您可以提供一个易于管理的前端管理站点，允许用户摆弄自己的对象，并且您不必记得输入我们上面谈到的特定ModelAdmin过滤器。

class FrontEndAdmin(models.ModelAdmin):
    def __init__(self, model, admin_site):
        self.model = model
        self.opts = model._meta
        self.admin_site = admin_site
        super(FrontEndAdmin, self).__init__(model, admin_site)

删除“删除”按钮:

    def get_actions(self, request):
        actions = super(FrontEndAdmin, self).get_actions(request)
        if 'delete_selected' in actions:
            del actions['delete_selected']
        return actions

禁止删除权限

    def has_delete_permission(self, request, obj=None):
        return False

过滤可以在管理站点上查看的对象:

    def get_queryset(self, request):
        if request.user.is_superuser:
            try:
                qs = self.model.objects.all()
            except AttributeError:
                qs = self.model._default_manager.get_queryset()
            return qs

        else:
            try:
                qs = self.model.objects.all()
            except AttributeError:
                qs = self.model._default_manager.get_queryset()

            if hasattr(self.model, ‘user’):
                return qs.filter(user=request.user)
            if hasattr(self.model, ‘porcupine’):
                return qs.filter(porcupine=request.user.porcupine)
            else:
                return qs

过滤管理站点上所有外键字段的选择:

    def formfield_for_foreignkey(self, db_field, request, **kwargs):
        if request.employee.is_superuser:
            return super(FrontEndAdmin, self).formfield_for_foreignkey(db_field, request, **kwargs)

        else:
            if hasattr(db_field.rel.to, 'user'):
                kwargs["queryset"] = db_field.rel.to.objects.filter(user=request.user)
            if hasattr(db_field.rel.to, 'porcupine'):
                kwargs["queryset"] = db_field.rel.to.objects.filter(porcupine=request.user.porcupine)
            return super(ModelAdminFront, self).formfield_for_foreignkey(db_field, request, **kwargs)