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005 Inbuilt and Custom Template Tag Filter in Django

Inbuilt and Custom Template Tag Filter in Django

Inbuilt Filter

  • One can use in-built filters directly
  • See an example of in-built filters below. data.number is passed from view and 99 is added to the passed value before displaying

index.html

<!DOCTYPE html>{% extends "mainApp/base.html" %}
    {% block body_block %}
        <div class="container">


            <div class="jumbotron">


                <h1>Welcome to a project about users</h1>


                <h2>{{ data.number|add:"99" }}</h2>


            </div>


        </div>


    {% endblock %}

Custom Filter

  • To create a custom filter as per your unique needs follow this process:
  • Inside app folder, create a folder named templatetags
  • Inside templatetags create a blank file named __init__.py. This tells python that templatetags is a package
  • Create another file named my_extras.py. This is where custom filters will be coded
  • The following example will show how to remove the word "World" from a string.

index.html

<!DOCTYPE html>{% extends "mainApp/base.html" %}
    {% block body_block %}
        <div class="container">


            <div class="jumbotron">


                <h1>Welcome to a project about users</h1>


                <h2>{{ data.text|cut:"World" }}</h2>


            </div>


        </div>


    {% endblock %}
  • And the function will be written in app > templatetags > my_extras.py
# Create Own Template Filter
from django import template

register = template.Library()


@register.filter(name='cut')
def cutout(value, arg):
    """    This cuts out all the values of 'arg' from the string!    :param value:    :param arg:    :return:    """    return value.replace(arg, '')

# register.filter('cut', cutout)
  • And that's how we do it

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