Django ModelFormSets

Creating and using Django ModelFormsets

For this article, let us consider a project named codingninjas having an application called Coding Ninjas Studio.

Refer to the below articles to check how to create a project and an application in Django.

• Creating a project with Django
• How to create an app in Django

Now, let's create a new file models.py in our Django application. We will make all the required Django models in this file.

from django.db import models
 
# Declaring a new model
class Coding Ninjas StudioModel(models.Model):
 
    # Fields in the model
    title = models.CharField(max_length = 200)
    description = models.TextField()
 
    # Using __str__() method
    def __str__(self):
            return self.title

You can also try this code with Online Python Compiler

Run Code

In the above code, we declared a new model Coding Ninjas StudioModel. This model has two fields title and description. In the model, we also added the __str__() method to change the display name of the model instance.

Now, we will create a simple Django FormSet of this form. So, let's move to views.py and add the following code.

from django.shortcuts import render
from .forms import Coding Ninjas StudioModel
from django.forms import formset_factory
 
def formset_view(request):
    context ={}
 
    # Creating a new Formset
    Coding Ninjas StudioFormSet = modelformset_factory(Coding Ninjas StudioModel)
    formset = Coding Ninjas StudioFormSet()
      
    # Adding the formset to context dictionary
    context['formset']= formset
    return render(request, "forms.html", context)

You can also try this code with Online Python Compiler

Run Code

In the above code, we created a simple Django formset named formset_view. Now, Let’s create forms.html file to render the formset through Django Template. Add the following code in template/forms.html.

<form method="POST" enctype="multipart/form-data">
            // Cross site sctripting tag
    {% csrf_token %}
    {{ formset.as_p }}
    <input type="submit" value="Submit Data">
</form>

You can also try this code with Online Python Compiler

Run Code

After creating the Django Template for Formset, let's add the Url in our Coding Ninjas Studio/urls.py file.

from django.urls import path
from .views import formset_view


urlpatterns = [
    path('/forms', forms, name=formset_view),
]

You can also try this code with Online Python Compiler

Run Code

Now, let's see the output by visiting https://localhost:8000/forms. 

Output

Creating Multiple forms using Django ModelFormsets

Django Formsets allows us to handle multiple instances of one form. We can create various forms easily with the help of extra attribute of Django Formsets. In Coding Ninjas Studio/views.py.

from django.shortcuts import render
from .forms import Coding Ninjas StudioModel
from django.forms import formset_factory
 
def formset_view(request):
    context ={}
 
    # Creating Formset and its three instances
    Coding Ninjas StudioFormSet = modelformset_factory(Coding Ninjas StudioModel, extra = 3)
    formset = Coding Ninjas StudioFormSet()
 
    # Add the formset to context dictionary
    context['formset']= formset
    return render(request, "forms.html", context)

You can also try this code with Online Python Compiler

Run Code

The keyword extra makes multiple copies of the same form in the above code. For creating three forms, we can set extra= 3. Now, let's visit https://localhost:8000/forms to see the changes.

Output

Handling Multiple forms using Django Formsets

Creating and using a form is easier than handling the entered data into those fields at the back end. This section will try to demonstrate how we can use the data of the Django ModelFormSets. For handling data Django ModelFromSets requires an extra argument {{ formset.management_data }}. We will add this extra argument in template/forms.html file.

<form method="POST" enctype="multipart/form-data">
    {% csrf_token %}
            {{ formset.management_data }}
    {{ formset.as_p }}
    <input type="submit" value="Submit Data">
</form>

You can also try this code with Online Python Compiler

Run Code

Now to check how and what kind of data is being rendered. We can edit formset_view to print the data. In Coding Ninjas Studio/view.py.

from django.shortcuts import render
from .forms import Coding Ninjas StudioModel
from django.forms import formset_factory
 
def formset_view(request):
    context ={}
 
    # Creating Formset and its 3 instances
    Coding Ninjas StudioFormSet = modelformset_factory(Coding Ninjas StudioModel, extra = 3)
    formset = Coding Ninjas StudioFormSet()
 
           # print formset data if it is valid
           if formset.is_valid():
                 for form in formset:
                     print(form.cleaned_data)
 
    # Add the formset to context dictionary
    context['formset']= formset
    return render(request, "forms.html", context)

You can also try this code with Online Python Compiler

Run Code

With the above code, we have successfully learned how to handle data in Django ModelformSets.

FAQs

1. What is the difference between formset_factory and modelformset_factory?
   formset_factory lets us render a bunch of forms together, but these forms are NOT necessarily related to the same database models, while modelformset_factory lets us edit/create a bunch of Django model objects together.
    
2. What is the role of fields in modelformset_factory()?
   This field defines the model form fields to be included in the model to create the Django Modelformset.

Key Takeaways

In this article, we learned about Django ModelFormsets. We created and used Django Modelformsets. We also multiple forms using Django Modelformsets. Finally, we learned to handle and manage data throughout multiple Django Modelformsets.

Don't stop here. Check out the blogs Best Django Books, Top 30 Basic Django Interview Questions: Part 1, and Top 30 Intermediate Django Interview Questions: Part 2.

We hope you found this blog helpful. Liked the blog? Then feel free to upvote and share it.