/ string索引处的TypeError必须是整数

Question

I am trying to make a custom made user creation form where user can type username,password and email to register in my site. but I am unable to debug this error. What kind of type error its referring to? I am using django 2.1 and postgresql 10.3 as db.

forms.py

from django import forms

class SignUpForm(forms.Form):
    username = forms.CharField(max_length=20)
    password = forms.CharField(widget=forms.PasswordInput(attrs={'placeholder':'password'}))
    password_confirmation = forms.CharField(widget=forms.PasswordInput(attrs={'placeholder':'password confirmation'}))
    email = forms.EmailField()

   def clean(self):
    password = self.cleaned_data.get('password')
    password_confirmation = self.cleaned_data.get('password_confirmation')
    print(password)
    print(password_confirmation)
    if password != password_confirmation:
        raise forms.ValidationError('Password Must Match')
    return password

urls.py

from django.urls import path
from .views import SignUpView
urlpatterns = [
    path('',SignUpView,name = 'signup')
]

views.py

from django.shortcuts import render
from .forms import SignUpForm
from django.contrib.auth.models import User
from django.shortcuts import HttpResponse

def SignUpView(request):
    if request.method == 'POST':
        form = SignUpForm(request.POST)
        if form.is_valid():
            username = form.cleaned_data['username']
            password = form.cleaned_data['password']
            email = form.cleaned_data['email']
            user = User(request,username=username,email=email)
            user.set_password(password)
            user.save()
            return HttpResponse('User Created')
    else:
        form =SignUpForm()
    return render(request,'signup.html',{'form':form})

TraceBack Error

Environment:

Request Method: POST
Request URL: http://127.0.0.1:8000/

Django Version: 2.0.5
Python Version: 3.6.3
Installed Applications:
['django.contrib.admin',
 'django.contrib.auth',
 'django.contrib.contenttypes',
 'django.contrib.sessions',
 'django.contrib.messages',
 'django.contrib.staticfiles',
 'account']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
 'django.contrib.sessions.middleware.SessionMiddleware',
 'django.middleware.common.CommonMiddleware',
 'django.middleware.csrf.CsrfViewMiddleware',
 'django.contrib.auth.middleware.AuthenticationMiddleware',
 'django.contrib.messages.middleware.MessageMiddleware',
 'django.middleware.clickjacking.XFrameOptionsMiddleware']



Traceback:

File "C:\Users\HP\AppData\Local\Programs\Python\Python36\lib\site-packages\django\core\handlers\exception.py" in inner
  35.             response = get_response(request)

File "C:\Users\HP\AppData\Local\Programs\Python\Python36\lib\site-packages\django\core\handlers\base.py" in _get_response
  128.                 response = self.process_exception_by_middleware(e, request)

File "C:\Users\HP\AppData\Local\Programs\Python\Python36\lib\site-packages\django\core\handlers\base.py" in _get_response
  126.                 response = wrapped_callback(request, *callback_args, **callback_kwargs)

File "C:\Users\HP\Desktop\muvi_2\account\views.py" in SignUpView
  10.             username = form.cleaned_data['username']

Exception Type: TypeError at /
Exception Value: string indices must be integers

Answer 1

You define the clean function as:

class SignUpForm(forms.Form):

    # ...

    def (self):
        password = self.cleaned_data.get('password')
        # ...
        

The super(..) however, is supposed to return the cleaned_data , so a dictionary. By overwriting it and returning the password , the "endproduct" of form.cleaned_data is no longer a dictionary-like object, but a string. Or like the documentation on form-cleaning [Django-doc] specifies:

The form subclass's clean() method can perform validation that requires access to multiple form fields. This is where you might put in checks such as "if field A is supplied, field B must contain a valid email address". This method can return a completely different dictionary if it wishes, which will be used as the cleaned_data .

So as a result, password will take the place of the cleaned_data (and it is not a dictionary-like object), so we can no longer obtain form.cleaned_data['username'] , since 'some_password'['username'] , of course makes no sense to Python.

We can rewrite the clean function by returning the self.cleaned_data at the end (by calling the super().clean() function for example):

from django import forms

class SignUpForm(forms.Form):
    # ...

    def (self):
        password = self.cleaned_data.get('password')
        password_confirmation = self.cleaned_data.get('password_confirmation')
        print(password)
        print(password_confirmation)
        if password != password_confirmation:
            raise forms.ValidationError('Password Must Match')
        

Additional error(s) : after the form is validated, you aim to create a User object with:

user = User(, username=username,email=email)

It is however not crear to me why you here use the request object. I think it should be:

user = User(username=username, email=email, password=)

You will also need to hash the password first, since otherwise it is a serious security threat . See the Django documentation on password hashing for more information.