django的from组件

1.后端
from django import froms
from  django import forms
from app import models
class RegForm(forms.Form):
      username=forms.CharField(max_length=8,min_length=3,label='用户名',
                               error_messages={
                                   'max_length':'用户名最长八位',
                                   'min_length':'用户名最短三位',
                                   'required':'用户名不能为空',
                               },widget=forms.widgets.TextInput(attrs={'class':'form-control'}))
      password=forms.CharField(max_length=8,min_length=3,label="密码",
                                error_messages={
                                    'max_length':'密码最长八位',
                                    'min_length':'密码最短三位',
                                    'required':'密码不能为空'
                                },widget=forms.widgets.PasswordInput(attrs={'class':'form-control'}))

      confirm_password = forms.CharField(max_length=8, min_length=3, label="确认密码",
                                 error_messages={
                                     'max_length': '密码最长八位',
                                     'min_length': '密码最短三位',
                                     'required': '密码不能为空'
                                 }, widget=forms.widgets.PasswordInput(attrs={'class':'form-control'}))

      email=forms.EmailField(label='邮箱',error_messages={
          'lnvalid':'邮箱格式错误',
          'required':'邮箱不能为空',
      },widget=forms.widgets.EmailInput(attrs={'class':'form-control'}))

      def clean_username(self):
          username=self.cleaned_data.get('username')
          user_obj=models.Userinfo.objects.filter(username=username).first()
          if user_obj:
              self.add_error('username','用户名已存在')
          else:
              return username

      def clean(self):
           password=self.cleaned_data.get('password')
           confir_password=self.cleaned_data.get('confirm_password')
           if not password == confir_password:
               self.add_error('confirm_password','两次密码不一致')
           else:
               return self.cleaned_data

　2　前端渲染

{% for foo in  form_obj%}
                        <div class="form-group">
                        <label for="{{ foo.auto_id }}">{{ foo.label }}</label>
                            {{ foo }}
                             <span></span>
                        </div>
                    {% endfor %}