如何在保存之前更改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

但我得到了错误.如何更改保存前userf.data['password']和userf.data['passwordrepeat']保存前的值？

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

如果您需要在保存之前对数据执行某些操作,只需创建一个函数,如:

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 _***nameofdata*的函数,其中nameofdata是字段的名称,因此如果要修改密码字段,则需要:

def clean_password(self):

如果你需要修改密码重复

def clean_passwordrepeat(self):

所以在那里,只需加密密码并返回加密密码.

我的意思是:

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

因此,当您对表单有效时,密码将被加密.

Answer 2

请参阅该save()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 3

如果您需要从POST填写表单,更改任何表单字段值并再次呈现表单,您将遇到问题.这是解决方案:

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})

Answer 4

覆盖_clean方法并将检查放入其中.你可以cleaned_data从那里修改.

例如:

def clean_password(self):
    new1 = self.cleaned_data['password']
    return new1

表单中的每个字段都有一个field_name_clean()由Django自动创建的方法.当你这样做时,会调用此方法form.is_valid().