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.

snippet
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.

snippet
<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
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.

Name Class HTML Input Empty value
BooleanField class BooleanField(**kwargs) CheckboxInput False
CharField class CharField(**kwargs) TextInput Whatever you've given as empty_value.
ChoiceField class ChoiceField(**kwargs) Select '' (an empty string)
DateField class DateField(**kwargs) DateInput None
DateTimeField class DateTimeField(**kwargs) DateTimeInput None
DecimalField class DecimalField(**kwargs) NumberInput None
EmailField class EmailField(**kwargs) EmailInput '' (an empty string)
FileField class FileField(**kwargs) ClearableFileInput None
ImageField class ImageField(**kwargs) ClearableFileInput None

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.

snippet
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

snippet
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

snippet
<!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

snippet
from django.contrib import admin
from django.urls import path
from myapp import views
urlpatterns = [
    path('admin/', admin.site.urls),
    path('index/', views.index),
]

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