Django Forms

Django provides a Form class which is used to create HTML forms. It describes a form and how it works and appears.

It is similar to the ModelForm class that creates a form by using the Model, but it does not require the Model.

Each field of the form class map to the HTML form <input> element and each one is a class itself, it manages form data and performs validation while submitting the form.

Lets see an example, in which we are creating some fields too.

from django import forms  

class StudentForm(forms.Form):  

    firstname = forms.CharField(label="Enter first name",max_length=50)  

    lastname  = forms.CharField(label="Enter last name", max_length = 100)  

A StudentForm is created that contains two fields of CharField type. Charfield is a class and used to create an HTML text input component in the form.

The label is used to set HTML label of the component and max_length sets length of an input value.

When rendered, it produces the following HTML to the browser.

<label for="id_firstname">Enter first name:</label>  

 <input type="text" name="firstname" required maxlength="50" id="id_firstname" />  

<label for="id_lastname">Enter last name:</label> <input type="text" name="lastname" required maxlength="100" id="id_lastname" /> 

Note: Django Form does not include <form> tags, or a submit button. We’ll have to provide those ourselves in the template.

Commonly used fields and their details are given in the below table.

NameClassHTML InputEmpty value
BooleanFieldclass BooleanField(**kwargs)CheckboxInputFalse
CharFieldclass CharField(**kwargs)TextInputWhatever you’ve given as empty_value.
ChoiceFieldclass ChoiceField(**kwargs)Select” (an empty string)
DateFieldclass DateField(**kwargs)DateInputNone
DateTimeFieldclass DateTimeField(**kwargs)DateTimeInputNone
DecimalFieldclass DecimalField(**kwargs)NumberInputNone
EmailFieldclass EmailField(**kwargs)EmailInput” (an empty string)
FileFieldclass FileField(**kwargs)ClearableFileInputNone
ImageFieldclass ImageField(**kwargs)ClearableFileInputNone

Let’s see a complete example to create an HTML form with the help of Django Form class.

Building a Form in Django

Suppose we want to create a form to get Student information, use the following code.

from django import forms  

class StudentForm(forms.Form):  

    firstname = forms.CharField(label="Enter first name",max_length=50)  

    lastname  = forms.CharField(label="Enter last name", max_length = 100) 

Put this code into the forms.py file.

Instantiating Form in Django

Now, we need to instantiate the form in views.py file. See, the below code.

// views.py

from django.shortcuts import render  

from myapp.form import StudentForm  

  

def index(request):  

    student = StudentForm()  

    return render(request,"index.html",{'form':student})  

Passing the context of form into index template that looks like this:

// index.html

<!DOCTYPE html>  

<html lang="en">  

<head>  

    <meta charset="UTF-8">  

    <title>Index</title>  

</head>  

<body>  

<form method="POST" class="post-form">  

        {% csrf_token %}  

        {{ form.as_p }}  

        <button type="submit" class="save btn btn-default">Save</button>  

</form>  

</body>  

</html> 

Provide the URL in urls.py

from django.contrib import admin  

from django.urls import path  

from myapp import views  

urlpatterns = [  

    path('admin/', admin.site.urls),  

    path('index/', views.index), 
  1. ]  

Run Server and access the form at browser by localhost:8000/index, and it will produce the following output.

django forms localhost index output

There are other output options though for the <label>/<input> pairs:

  • {{ form.as_table }} will render them as table cells wrapped in <tr> tags
  • {{ form.as_p }} will render them wrapped in <p> tags
  • {{ form.as_ul }} will render them wrapped in <li> tags

Note: that we’ll have to provide the surrounding <table> or <ul> elements yourself.


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