Python Django form 组件动态从数据库取choices数据实例

from django.db import models
 
class UserInfo(models.Model):
  username = models.CharField(max_length=16)
  password = models.CharField(max_length=16)
  mobile = models.CharField(max_length=11)
 
class City(models.Model):
  name = models.CharField(max_length=16, null=False, unique=True)

from django.shortcuts import render, HttpResponse
from app01 import models
from django import forms
from django.forms import widgets
from django.core.validators import RegexValidator
from django.core.exceptions import ValidationError
class RegForm(forms.Form):
username = forms.CharField(
min_length=5,
label="用户名",
error_messages={
"min_length": "用户名不能小于5位！",
"required": "该字段不能为空"
},
widget=widgets.TextInput(attrs={"class": "form-control"})
)
password = forms.CharField(
min_length=6,
label="密码",
error_messages={
"min_length": "密码不能少于6位！",
"required": "该字段不能为空"
},
widget=widgets.PasswordInput(attrs={"class": "form-control"}, render_value=True)
)
re_password = forms.CharField(
min_length=6,
label="确认密码",
error_messages={
"required": "该字段不能为空"
},
widget=widgets.PasswordInput(attrs={"class": "form-control"}, render_value=True)
)
mobile = forms.CharField(
label="手机号",
# 自定义正则匹配规则
validators=[
RegexValidator(r'^[0-9]+$', "手机号必须是数字"), # 判断手机号是否为数字
RegexValidator(r'^1[3-9][0-9]{9}$', "手机格式有误") # 判断手机号是否为 1 和 3-9 开头的十一位数
],
error_messages={
"required": "该字段不能为空",
},
widget=widgets.TextInput(attrs={"class": "form-control"})
)
city = forms.ChoiceField(
choices=models.City.objects.values_list("id", "name"),
label="城市",
initial=2,
widget=widgets.Select()
)
# 重写父类的 __init__ 方法
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.fields['city'].widget.choices = models.City.objects.values_list("id", "name")
# 判断用户名信息
def clean_username(self):
value = self.cleaned_data.get("username")
if "admin" in value:
raise ValidationError("用户名不能含有敏感信息")
# 重写父类的 clean 方法
def clean(self):
password = self.cleaned_data.get("password")
re_password = self.cleaned_data.get("re_password")
if re_password != password:
self.add_error("password", ValidationError("两次密码不一致"))
self.add_error("re_password", ValidationError("两次密码不一致"))
raise ValidationError("两次密码不一致")
return self.cleaned_data
def reg2(request):
form_obj = RegForm() # GET 请求
if request.method == "POST":
form_obj = RegForm(request.POST)
# 让 form 来帮我们进行校验
if form_obj.is_valid():
# 如果通过校验
# 所有经过校验的数据都保存在 form_obj.cleaned_data
print(form_obj.cleaned_data)
models.UserInfo.objects.create(**form_obj.cleaned_data)
return HttpResponse("注册成功")
return render(request, "reg2.html", {"form_obj": form_obj})