How to See if a String Contains Another String in Django Template

This is my code in a template.

{% if 'index.html' in  "{{ request.build_absolute_uri  }}" %} 
	'hello'
{% else %}     	
	'bye'
{% endif %}

Now my url value currently is "http://127.0.0.1:8000/login?next=/index.html"

Even though "index.html" is there in the string it still prints bye.

When I run the same code in a python shell it works. Not sure what the mistake is.

Try removing the extra {{...}} tags and the "..." quotes around request.build_absolute_uri, it worked for me.

Since you are already within an {% if %} tag, there is no need to surround request.build_absolute_uri with {{...}} tags.

{% if 'index.html' in request.build_absolute_uri %}
    hello
{% else %}
    bye
{% endif %}

Because of the quotes you are literally searching the string "{{ request.build_absolute_uri }}" and not the evaluated Django tag you intended.

Maybe too late but here is a lightweight version :

{{ 'hello 'if 'index.html' in request.build_absolute_uri else 'bye' }}

This can be tested with Jinja:

>>> from jinja2 import Template
>>> t = Template("{{ 'hello 'if 'index.html' in request.build_absolute_uri else 'bye' }}")
>>> request = {}
>>> request['build_absolute_uri']='...index.html...'
>>> t.render(request=request)
'hello '
>>> request['build_absolute_uri']='something else...'
>>> t.render(request=request)
'bye'
>>> 

I am adding the negative option of "not contains":

{% if 'index.html' not in request.build_absolute_uri %}
    hello
{% else %}
    bye
{% endif %}

And:

{{ 'hello 'if 'index.html' not in request.build_absolute_uri else 'bye' }}