Retrieving data from an array of check boxes in a Django template - django

Question

In a Django template, I'm displaying some usernames (or unames) along with check boxes like so:
<form method="POST" action="{% url 'process_unames' %}">
{% csrf_token %}
{% for name in unames %}
<input type="checkbox" name="target{{ forloop.counter0 }}" value="{{ unames|index:forloop.counter0 }}" checked>{{ name }}<br>
{% endfor %}
<button name="duration" value="{{ value }}" type="submit">Submit</button>
</form>
And then in the function process_unames, I'm trying to retrieve all checked unames via:
def process_unames(request, *args, **kwargs):
uname_list = request.POST.getlist('unames')
This is consistently yielding an empty list, regardless of which uname I check or uncheck. How do I fix this? An illustrative example would be great.
In case it matters, I haven't declared any form in forms.py with this Django template. Moreover, note that index is a custom template tag which does the following (and I can vouch it's correctly working):
from django.template.defaulttags import register
#register.filter(name='index')
def index(List, i):
return List[int(i)]

Answer 1

You are checking the wrong variable. You access the input by its name.
So for a single value you would retrieve the data for a form like this
<input type="checkbox" name="user_name" value={{uname}}>
via
request.POST.get('user_name')
See: https://docs.djangoproject.com/en/1.10/topics/forms/#the-work-that-needs-to-be-done
And if you have loop, you still give each relevant input the same name and use request.POST.getlist() to access the values as a list.
See: https://stackoverflow.com/a/23470119/630877

Answer 2

You don't have any fields called "unames" in the template. You have a bunch of unrelated checkboxes called "targetX" where X is a number. Replace that with just name="unames" and your code will work.
Note two things: firstly, you should be using Django's forms framework; and secondly, your filter is pointless because {{ name }} would already by the value in unames, since that is what you are iterating over (and, indeed, you are already using that as the label).
{% for name in unames %}
<input type="checkbox" name="unames" value="{{ name }}" checked>{{ name }}<br>
{% endfor %}