08. ফর্ম ভ্যালিডেশন

class MyForm(forms.Form):
    age = forms.IntegerField()

    def clean_age(self):
        age = self.cleaned_data['age']
        if age < 18 or age > 120:
            raise forms.ValidationError("Age must be between 18 and 120.")

class MyForm(forms.Form):
    password = forms.CharField(max_length=100)
    password_confirm = forms.CharField(max_length=100)

    def clean(self):
        cleaned_data = super().clean()
        password = cleaned_data.get('password')
        password_confirm = cleaned_data.get('password_confirm')

        if password != password_confirm:
            raise forms.ValidationError({"password_confirm": "Passwords must match."})

        return cleaned_data

from django import forms
from .models import MyModel

class MyModelForm(forms.ModelForm):
    class Meta:
        model = MyModel
        fields = ['name']

    def clean_name(self):
        name = self.cleaned_data['name']
        if len(name) < 5:
            raise forms.ValidationError("Name must be at least 5 characters long.")
        return name

from django import forms
from .models import MyModel

class MyModelForm(forms.ModelForm):
    class Meta:
        model = MyModel
        fields = ['name', 'age']

    def clean(self):
        cleaned_data = super().clean()
        password = cleaned_data.get('password')
        password_confirm = cleaned_data.get('password_confirm')

        if password != password_confirm:
            raise forms.ValidationError({"password_confirm": "Passwords must match."})

        return cleaned_data

form = MyForm(request.POST)

if form.is_valid():
    # Process the form data
else:
    # Handle the form errors

if not form.is_valid():
    for field, errors in form.errors.items():
        for error in errors:
            print(f"{field}: {error}")

if request.method == 'POST':
    # Create an instance of the form with the posted data
    my_form = MyForm(request.POST, request.FILES)

# Check if the form is multipart
if my_form.is_multipart():
    print("The form is multipart.")
else:
    print("The form is not multipart.")

from django import forms

class MyForm(forms.Form):
    text_field = forms.CharField()
    file_field = forms.FileField()

# In a view or somewhere else
if request.method == 'POST':
    # Create an instance of the form with the posted data
    my_form = MyForm(request.POST, request.FILES)

    # Check if the form is valid and multipart
    if my_form.is_valid() and my_form.is_multipart():
        # Form is valid, process the data
        text_data = my_form.cleaned_data['text_field']
        file_data = my_form.cleaned_data['file_field']

        # Additional processing logic

        print("Form is valid and multipart.")
    else:
        # Form is not valid or not multipart, handle errors
        print("Form is not valid or not multipart.")
else:
    # Create an empty form for GET requests
    my_form = MyForm()

# Check if the form is multipart
if my_form.is_multipart():
    print("The form is multipart.")
else:
    print("The form is not multipart.")

my_form = MyForm()

# Check if the form data has changed
if my_form.has_changed():
    print("Form data has changed.")
else:
    print("Form data has not changed.")