Numeric for loop in Django templates

Question

How do I write a numeric for loop in a Django template? I mean something like

for i = 1 to n

Answer 1

I've used a simple technique that works nicely for small cases with no special tags and no additional context. Sometimes this comes in handy

{% for i in '0123456789'|make_list %}
    {{ forloop.counter }}
{% endfor %}

Answer 2

{% with ''|center:n as range %}
{% for _ in range %}
    {{ forloop.counter }}
{% endfor %}
{% endwith %}

Answer 3

Unfortunately, that's not supported in the Django template language. There are a couple of suggestions, but they seem a little complex. I would just put a variable in the context:

...
render_to_response('foo.html', {..., 'range': range(10), ...}, ...)
...

and in the template:

{% for i in range %}
     ...
{% endfor %}

Answer 4

My take on this issue, i think is the most pythonic. Create a my_filters.py in your apps templatetags directory.

@register.filter(name='times') 
def times(number):
    return range(number)

Usage in your template:

{% load my_filters %}
{% for i in 15|times %}
    <li>Item</li>
{% endfor %}

Answer 5

You can pass a binding of

{'n' : range(n) }

to the template, then do

{% for i in n %}
...
{% endfor %}

Note that you'll get 0-based behavior (0, 1, ... n-1).

(Updated for Python3 compatibility)

Answer 6

Maybe like this?

{% for i in "x"|rjust:"100" %}
...
{% endfor %}

Answer 7

I'm just taking the popular answer a bit further and making it more robust. This lets you specify any start point, so 0 or 1 for example. It also uses python's range feature where the end is one less so it can be used directly with list lengths for example.

@register.filter(name='range')
def filter_range(start, end):
    return range(start, end)

Then in your template just include the above template tag file and use the following:

{% load myapp_filters %}

{% for c in 1|range:6 %}
    {{ c }}
{% endfor %}

Now you can do 1-6 instead of just 0-6 or hard coding it. Adding a step would require a template tag, this should cover more uses cases so it's a step forward.

Answer 8

I tried very hard on this question, and I find the best answer here: (from how to loop 7 times in the django templates)

You can even access the idx!

views.py:

context['loop_times'] = range(1, 8)

html:

{% for i in loop_times %}
        <option value={{ i }}>{{ i }}</option>
{% endfor %}

Answer 9

You don't pass n itself, but rather range(n) [the list of integers from 0 to n-1 included], from your view to your template, and in the latter you do {% for i in therange %} (if you absolutely insist on 1-based rather than the normal 0-based index you can use forloop.counter in the loop's body;-).

Answer 10

You should use "slice" in template, a example like this:

in views.py

contexts = {
    'ALL_STORES': Store.objects.all(),
}

return render_to_response('store_list.html', contexts, RequestContext(request, processors=[custom_processor]))

in store_list.html:

<ul>
{% for store in ALL_STORES|slice:":10" %}
    <li class="store_item">{{ store.name }}</li>
{% endfor %}
</ul>

Answer 11

Just incase anyone else comes across this question… I've created a template tag which lets you create a range(...): http://www.djangosnippets.org/snippets/1926/

Accepts the same arguments as the 'range' builtin and creates a list containing
the result of 'range'.

Syntax:
    {% mkrange [start,] stop[, step] as context_name %}

For example:
    {% mkrange 5 10 2 as some_range %}
    {% for i in some_range %}
      {{ i }}: Something I want to repeat\n
    {% endfor %}

Produces:
    5: Something I want to repeat 
    7: Something I want to repeat 
    9: Something I want to repeat

Answer 12

This method supports all the functionality of the standard range([start,] stop[, step]) function

<app>/templatetags/range.py

from django import template

register = template.Library()


@register.filter(name='range')
def _range(_min, args=None):
    _max, _step = None, None
    if args:
        if not isinstance(args, int):
            _max, _step = map(int, args.split(','))
        else:
            _max = args
    args = filter(None, (_min, _max, _step))
    return range(*args)

Usage:

{% load range %}

<p>stop 5
{% for value in 5|range %}
{{ value }}
{% endfor %}
</p>

<p>start 5 stop 10
{% for value in 5|range:10 %}
{{ value }}
{% endfor %}
</p>

<p>start 5 stop 10 step 2
{% for value in 5|range:"10,2" %}
{{ value }}
{% endfor %}
</p>

Output

<p>stop 5
0 1 2 3 4
</p>

<p>start 5 stop 10
5 6 7 8 9
</p>

<p>start 5 stop 10 step 2
5 7 9
</p>

Answer 13

This essentially requires a range function. A Django feature ticket was raised (https://code.djangoproject.com/ticket/13088) for this but closed as "won't fix" with the following comment.

My impression of this idea is that it is trying to lead to programming in the template. If you have a list of options that need to be rendered, they should be computed in the view, not in the template. If that's as simple as a range of values, then so be it.

They have a good point - Templates are supposed to be very simple representations of the view. You should create the limited required data in the view and pass to the template in the context.

Answer 14

{% for _ in ''|center:13 %}
    {{ forloop.counter }}
{% endfor %}

Answer 15

If the number is coming from a model, I found this to be a nice patch to the model:

def iterableQuantity(self):
    return range(self.quantity)

Answer 16

For those who are looking to simple answer, just needing to display an amount of values, let say 3 from 100 posts for example just add {% for post in posts|slice:"3" %} and loop it normally and only 3 posts will be added.

Answer 17

This shows 1 to 20 numbers:

{% for i in "x"|rjust:"20"|make_list %}
 {{ forloop.counter }}
{% endfor %}

also this can help you: (count_all_slider_objects come from views)

{% for i in "x"|rjust:count_all_slider_objects %}
  {{ forloop.counter }}
{% endfor %}

or

  {% with counter=count_all_slider_objects %}
    {% if list_all_slider_objects %}
      {%  for slide in list_all_slider_objects %}
        {{forloop.counter|add:"-1"}}
        {% endfor%}
      {% endif %}
    {% endwith %}

Answer 18

You can pass range(n) instead of n in the context in views.py. This will give you an iterable list.

context['range']= range(n)

Then you can iterate in your template this way:

{% for i in range %}
   <!-- your code -->
{% endfor %}

Answer 19

If you work with queryset you can cap the number of elements with if. Assume that you need to list 5 items:

{% for  item in queryset %}
  {% if forloop.counter < 6 %}
   {{ forloop.counter}}.{{item}}
  {% endif %}
{% endfor %}

If you need just number range, I think its better to create a list or tuple on view part and then push it to the template.

On view:

iteration = [item for item in range(10)]
context= {'iteration':iteration}

On Template:

{% for  item in iteration %}
  {{ forloop.counter}}.{{item}}
{% endfor %}

Answer 20

{% for i in range(10) %}
   {{ i }}

{% endfor %}