Django Forms CheckboxInput在现有数据库中的Y/N String字段上

Question

我对Django比较陌生，我正在制作一个连接到现有MySQL数据库的表单。

我想做的是创建一个国家/地区的维护页面。我的数据库中的一个字段是eu_member_state。

我在这里要做的是为这个字段创建一个复选框，这样我就可以为最近退出欧盟的英国取消选中它。

class CountryForm(forms.ModelForm):
class Meta():
model = Countries
fields = '__all__'
widgets = {
'eu_member_state': forms.CheckboxInput()
}

复选框确实出现在我的表单上，但我如何使它与我的数据库对话？如何仅当数据库值为"Y"时才选中此复选框，以及如何在保存时将其写回数据库，因此选中时为"Y"，未选中时为"N"？

这是型号代码：

from django.db import models
class Countries(models.Model):
country = models.CharField(unique=True, max_length=3)
descr = models.CharField(max_length=50, blank=True, null=True)
descrshort = models.CharField(max_length=20, blank=True, null=True)
country_2char = models.CharField(max_length=2, blank=True, null=True)
eu_member_state = models.CharField(max_length=1, blank=False, null=False, default='N')
class Meta:
db_table = 'countries'
verbose_name_plural = "countries"
def __str__(self):
return self.descr

Answer 1

我通过创建一个自定义的CheckboxInput字段并在forms.py.中初始化它来解决这个问题

class CountryForm(forms.ModelForm):
eu_member_state_flag = forms.BooleanField(required=False,label='EU member state')
class Meta():
model = Countries
exclude = ('eu_member_state',)

def __init__(self, *args, **kwargs):
super(CountryForm, self).__init__(*args, **kwargs)
if self.instance.eu_member_state == "Y":
flag_value = True
else:
flag_value = False
self.initial['eu_member_state_flag'] = flag_value

然后在views.py中，我获取CheckboxInput字段的值，并将其转换为"Y"或"N"。

class UpdateCountryView(LoginRequiredMixin,UpdateView):
login_url= '/login/'
redirect_field_name = 'tour_admin/countries_list.html'
form_class = CountryForm
model = Countries
def form_valid(self, form):
if form.is_valid():
data = form.cleaned_data
if data['eu_member_state_flag']:
data['eu_member_state'] = 'Y'
self.object.eu_member_state = 'Y'
else:
data['eu_member_state'] = 'N'
self.object.eu_member_state = 'N'
self.object.save()
return HttpResponseRedirect(self.get_success_url())
def get_success_url(self):
return reverse('countries_list')