How to get information from one Django models object?

Question

today I'm trying to get and print all my users emails, who had chose selection "Value1".

This is how my model.py looks like:

from django.db import models

class Vartotojas(models.Model):
    email = models.EmailField()
    option = models.CharField(max_length=30)

Forms.py :

from django import forms
from emailai.models import Vartotojas

class VartotojasForm(forms.Form):
    email = forms.EmailField(max_length=100)
    my_field = forms.MultipleChoiceField(choices=(('Value1','Value1'),('Value2','Value2')), widget=forms.CheckboxSelectMultiple())
    
    def save(self):
        mymodel = Vartotojas(
        email=self.cleaned_data['email'],
        option=self.cleaned_data['my_field'],
        )
        mymodel.save()

And finally my views.py "

from django.shortcuts import render
from django.http import HttpResponse
from django.http import HttpResponseRedirect
from emailai.models import Vartotojas
from renginiai.forms import VartotojasForm

def name(request):
    if request.method == 'POST':
        form = VartotojasForm(request.POST)
        if form.is_valid():
            a = Vartotojas.objects.filter(option="u'Value1'") # How to do it right?
            # Now How To Get those object emails?
            new_user = form.save()
            return render(request, "Vartotojas-result.html", {
        'form': form, #BLABLABLA,
    })
    else:
        form = VartotojasForm()
    return render(request, "Vartotojas-form.html", {
        'form': form,
    })

I commented my questions inside my views.py. I hope you will be able to help me. Thank you in advance!

I re-write my code with getlist. Now it looks like this:

views.py :

if form.is_valid():
            email = form.cleaned_data['email']
            option = request.POST.getlist('my_field')
            new_user = form.save(email, option)

forms.py:

email = forms.EmailField(max_length=100)
my_field = forms.MultipleChoiceField(choices=(('Value1','Value1'),('Value2','Value2')), widget=forms.CheckboxSelectMultiple())
    
    def save(self, email, option):
        mymodel = Vartotojas(
        email=email,
        option = option,
        )
        mymodel.save()

As you see I pasted just most important places. By the way, users can choose 2 values, that's why I use checkbox. But still it not working.

ur filtering all values with option='Value1' right? now u have list of objects that satisfy the option. u can loop over that list and get the email attribute by using the dot operator for example, a[i].email where i is the index of the list a. — ueg1990, Feb 24 '14 at 19:54
You would have to add it to the dictionary you're passing to `render`, but don't do what the comment suggests; my answer below will give you the list directly and save the loop. — Tom, Feb 24 '14 at 20:04
`option="u'Value1'"` looks very strange. You don't mean just `option=u'Value1'`? — Kevin Christopher Henry, Feb 24 '14 at 20:05

Tom · Accepted Answer · 2014-02-24T20:22:24.987

2

I believe you want to use the values_list property like so:

Vartotojas.objects.filter(option=u"Value1").values_list("email", flat=True)

to get a list of all email addresses. You may also want to apply a distinct() to that if you're not already preventing duplicates. On a side note, look into ModelForms: it looks like that would save you a fair bit of the time/ code you have written for dealing with this. You could create a ModelForm based on your Vartotojas object and not have to write the explicit save() method you have.

edited Feb 24 '14 at 20:22

answered Feb 24 '14 at 20:02

Tom

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Thanks, you get me on the way. However, somewhere is mistake. In my opinion: option="u'Value1'". I think, i have to write "u'Value1'" somehow different, because now I get empty list, but I know that in it should be atleast 5 emails. – Irmantas Želionis Feb 24 '14 at 20:10
Sorry, I should have caught that: you want the `u` on the outside of the string, not inside it. I've updated my code to reflect that. – Tom Feb 24 '14 at 20:23
[`distinct()`](https://docs.djangoproject.com/en/dev/ref/models/querysets/#distinct) adds `DISTINCT` to the query, which is standard SQL and supported in all the databases Django typically works with. – Tom Feb 24 '14 at 20:27
Open your database table and see if there are records with that value in them. It might be helpful to play with the query filtering in the [Django shell](https://docs.djangoproject.com/en/dev/ref/django-admin/#shell) rather than trying to figure it out in the view. Alternatively, you can try using [pdb](http://stackoverflow.com/questions/4228637/getting-started-with-the-python-debugger-pdb) and a breakpoint to debug the problem. – Tom Feb 24 '14 at 20:30
Using the shell, it would be good to find out if `Vartotojas.objects.filter(option=u"Value1")` returns any records. Also try it without the `u`, `Vartotojas.objects.filter(option="Value1")` – Tom Feb 24 '14 at 20:31
mhm it returns empty list, but in my admin interface I have objects with value1 http://www.part.lt/perziura/5df19523db16eb221991da731d7a8dd9392.png – Irmantas Želionis Feb 24 '14 at 20:39
Ah, no you don't: you have a record with a list in it. I'm guessing `self.cleaned_data['my_field']` refers to checkboxes in the form. If they are checkboxes with the same name, Django will organize that into a list. To properly handle the checkboxes, you'd want [getlist](http://stackoverflow.com/questions/10276753/get-the-list-of-checkbox-post-in-django-views), but I think you may want to change to radio buttons on the front-end if users are only supposed to select one. – Tom Feb 24 '14 at 21:25

How to get information from one Django models object?

views.py :

1 Answers1