how create a #username by taking username from registration form - django

Question

i have setup the forms in the frontend what i want is that any User if gives his username for example username-> helloworld then it is interpreted as #helloworld and then this form with changed #username should be saved in the database so that i can use it afterwards.....
i am a noob in django framework .
i have been trying since last 2 days to find a answer here and by using google but unable to find a helpful answer
here is my ->forms.py
from django.forms import ModelForm
from django.contrib.auth.forms import UserCreationForm
from django.contrib.auth.models import User
class SignUpForm(UserCreationForm):
class Meta:
model = User
fields = ['first_name','last_name','username', 'email', 'password1', 'password2']
this is my -> views.py file
from django.shortcuts import render, redirect
from django.contrib.auth import authenticate
from django.contrib import messages
from django.contrib.auth.models import User
from .forms import SignUpForm
from django.contrib.auth import get_user_model
from django.contrib.auth.tokens import default_token_generator
from django.contrib.sites.shortcuts import get_current_site
from django.core.mail import EmailMessage
from django.http import HttpResponse
from django.template.loader import render_to_string
from django.utils.encoding import force_bytes
from django.utils.http import urlsafe_base64_encode, urlsafe_base64_decode
UserModel = get_user_model()
#index and signin def have been removed because it is out of context of question
def signup(request):
if request.user.is_authenticated:
return redirect('index')
else:
form = SignUpForm()
if request.method == 'POST':
form = SignUpForm(request.POST)
if form.is_valid():
user = form.save(commit=False)
User.username = "#{}".format(User.username)
user.is_active = False
user = form.save
user.save()
current_site = get_current_site(request)
mail_subject = 'Activate your account.'
message = render_to_string('activation_mail.html', {
'user': user,
'domain': current_site.domain,
'uid': urlsafe_base64_encode(force_bytes(user.pk)),
'token': default_token_generator.make_token(user),
})
to_email = form.cleaned_data.get('email')
email = EmailMessage(
mail_subject, message, to=[to_email]
)
email.send()
return HttpResponse('Please confirm your email address to complete the registration')
else:
form = SignUpForm()
return render(request, 'signup.html', {'form': form})

Answer 1

Just override your form's save method to alter the data before saving.
class SignUpForm(UserCreationForm):
class Meta:
model = User
fields = ['first_name','last_name','username', 'email', 'password1', 'password2']
def save(self, *args, **kwargs):
self.instance.username = f"#{self.instance.username}"
return super().save(*args, **kwargs)