保存前如何更改Django表单字段值？

Question

if request.method == 'POST':
    userf = UsersModelForm(request.POST)
    username = userf.data['username']
    password = userf.data['password']
    passwordrepeat = userf.data['passwordrepeat']
    email = userf.data['email']

我试过这个：

    tempSalt = bcrypt.gensalt()
    password = bcrypt.hashpw(password,tempSalt)
    passwordrepeat = bcrypt.hashpw(passwordrepeat,tempSalt)

    userf.data['password'] = password
    userf.data['passwordrepeat'] = passwordrepeat

但我错了。如何在保存前更改userf.data['password']和userf.data['passwordrepeat']的值？

错误：

AttributeError at /register

This QueryDict instance is immutable

Request Method:     POST
Request URL:    http://127.0.0.1:8000/register
Django Version:     1.3.1
Exception Type:     AttributeError
Exception Value:    

This QueryDict instance is immutable

Exception Location:     /usr/local/lib/python2.6/dist-packages/django/http/__init__.py in _assert_mutable, line 359
Python Executable:  /usr/bin/python
Python Version:     2.6.6
Python Path:    

['/home/user1/djangoblog',
 '/usr/lib/python2.6',
 '/usr/lib/python2.6/plat-linux2',
 '/usr/lib/python2.6/lib-tk',
 '/usr/lib/python2.6/lib-old',
 '/usr/lib/python2.6/lib-dynload',
 '/usr/local/lib/python2.6/dist-packages',
 '/usr/lib/python2.6/dist-packages',
 '/usr/lib/python2.6/dist-packages/gst-0.10',
 '/usr/lib/pymodules/python2.6',
 '/usr/lib/pymodules/python2.6/gtk-2.0']

Answer 1

请参阅^{}方法的文档

if request.method == 'POST':
    userf = UsersModelForm(request.POST)
    new_user = userf.save(commit=False)

    username = userf.cleaned_data['username']
    password = userf.cleaned_data['password']
    passwordrepeat = userf.cleaned_data['passwordrepeat']
    email = userf.cleaned_data['email']

    new_user.password = new1
    new_user.passwordrepeat = new2

    new_user.save()

Answer 2

如果在保存之前需要对数据执行某些操作，只需创建一个如下函数：

def clean_nameofdata(self):
    data = self.cleaned_data['nameofdata']
    # do some stuff
    return data

您只需要创建一个名为**clean\u**nameofdata*的函数，其中nameofdata是字段的名称，因此如果要修改密码字段，您需要：

def clean_password(self):

如果需要修改密码repeat

def clean_passwordrepeat(self):

所以在里面，只要加密你的密码并返回加密的密码。

我是说：

def clean_password(self):
    data = self.cleaned_data['password']
    # encrypt stuff
    return data

所以当你有效的时候，密码会被加密。

Answer 3

如果需要从POST填写表单、更改任何表单字段值并再次呈现表单，则会出现问题。 以下是解决方案：

class StudentSignUpForm(forms.Form):
  step = forms.IntegerField()

  def set_step(self, step):
    data = self.data.copy()
    data['step'] = step
    self.data = data

然后：

form = StudentSignUpForm(request.POST)
if form.is_valid() and something():
  form.set_step(2)
  return  render_to_string('form.html', {'form': form})