django----利用Form 实现两次密码输入是否一样 ( 局部钩子和全局钩子 )

from django import forms  # 导入表单模块
from django.core.exceptions import ValidationError

class RegisterForm(forms.Form): # 自定义表单类，并继承forms.Form
  email = forms.EmailField(widget=forms.EmailInput(
      attrs={"class": "form-control"}))

  username = forms.CharField(min_length=4, max_length=12, widget=forms.TextInput(
      attrs={"class": "form-control"}))

  password = forms.CharField(min_length=6, widget=forms.PasswordInput(
      attrs={"class": "form-control"}))

  password2 = forms.CharField(min_length=6, widget=forms.PasswordInput(
      attrs={"class": "form-control"}))

  valid_code = forms.CharField(widget=forms.TextInput(
      attrs={"class": "form-control"}))

  def __init__(self, request, *args, **kwargs):
      # 如果需要额外接收参数，要重写构造器函数
      # 这里额外接收一个参数，用于从request.sesssion中提取之前保存的验证码
      super(RegisterForm,self).__init__(*args, **kwargs)
      self.request = request

  # 自定义方法（局部钩子），密码必须包含字母和数字
  def clean_password(self):
      if self.cleaned_data.get('password').isdigit() or self.cleaned_data.get('password').isalpha():
          raise ValidationError('密码必须包含数字和字母')
      else:
          return self.cleaned_data['password']

  def clean_valid_code(self):  # 检验验证码正确；之前生成的验证码保存在了了session中
      if self.cleaned_data.get('valid_code').upper() == self.request.session.get('valid_code'):
          return self.cleaned_data['valid_code']
      else:
          raise ValidationError('验证码不正确')

  # 自定义方法（全局钩子, 检验两个字段），检验两次密码一致;
  def clean(self):
      if self.cleaned_data.get('password') != self.cleaned_data.get('password2'):
          raise ValidationError('密码不一致')
      else:
          return self.cleaned_data

  # 注意，上面的字典取值用get, 因为假如在clean_password中判断失败，那么没有返回值，最下面的clean方法直接取值就会失败s