问题
I'm beginner in Django/Python and I need to create a multiple select form. I know it's easy but I can't find any example. I know how to create a CharField with a widget but I get confused of all the options inside fields.py.
For example I don't know which one of the followings is best for a multiple select form.
'ChoiceField', 'MultipleChoiceField',
'ComboField', 'MultiValueField',
'TypedChoiceField', 'TypedMultipleChoiceField'
And here is the form I need to create.
<form action="" method="post" accept-charset="utf-8">
<select name="countries" id="countries" class="multiselect" multiple="multiple">
<option value="AUT" selected="selected">Austria</option>
<option value="DEU" selected="selected">Germany</option>
<option value="NLD" selected="selected">Netherlands</option>
<option value="USA">United States</option>
</select>
<p><input type="submit" value="Continue →"></p>
</form>
EDIT:
One more small question. If I want to add to each option one more attribute like data:
<option value="AUT" selected="selected" data-index=1>Austria</option>
How can I do it?
Thanks for any help!
回答1:
I think CheckboxSelectMultiple should work according to your problem.
In your forms.py, write the below code:
from django import forms
class CountryForm(forms.Form):
OPTIONS = (
("AUT", "Austria"),
("DEU", "Germany"),
("NLD", "Neitherlands"),
)
Countries = forms.MultipleChoiceField(widget=forms.CheckboxSelectMultiple,
choices=OPTIONS)
In your views.py, define the following function:
def countries_view(request):
if request.method == 'POST':
form = CountryForm(request.POST)
if form.is_valid():
countries = form.cleaned_data.get('countries')
# do something with your results
else:
form = CountryForm
return render_to_response('render_country.html', {'form': form},
context_instance=RequestContext(request))
In your render_country.html:
<form method='post'>
{% csrf_token %}
{{ form.as_p }}
<input type='submit' value='submit'>
</form>
回答2:
I did it in this way :
forms.py
class ChoiceForm(ModelForm):
class Meta:
model = YourModel
def __init__(self, *args, **kwargs):
super(ChoiceForm, self).__init__(*args, **kwargs)
self.fields['countries'] = ModelChoiceField(queryset=YourModel.objects.all()),
empty_label="Choose a countries",)
urls.py
from django.conf.urls.defaults import *
from django.views.generic import CreateView
from django.core.urlresolvers import reverse
urlpatterns = patterns('',
url(r'^$',CreateView.as_view(model=YourModel, get_success_url=lambda: reverse('model_countries'),
template_name='your_countries.html'), form_class=ChoiceForm, name='model_countries'),)
your_countries.html
<form action="" method="post">
{% csrf_token %}
{{ form.as_table }}
<input type="submit" value="Submit" />
</form>
It is works fine in my example, If you need something more, just ask me!!
回答3:
Regarding to my second question this is the solution. An extending class:
from django import forms
from django.utils.encoding import force_unicode
from itertools import chain
from django.utils.html import escape, conditional_escape
class Select(forms.Select):
"""
A subclass of Select that adds the possibility to define additional
properties on options.
It works as Select, except that the ``choices`` parameter takes a list of
3 elements tuples containing ``(value, label, attrs)``, where ``attrs``
is a dict containing the additional attributes of the option.
"""
def render_options(self, choices, selected_choices):
def render_option(option_value, option_label, attrs):
option_value = force_unicode(option_value)
selected_html = (option_value in selected_choices) and u' selected="selected"' or ''
attrs_html = []
for k, v in attrs.items():
attrs_html.append('%s="%s"' % (k, escape(v)))
if attrs_html:
attrs_html = " " + " ".join(attrs_html)
else:
attrs_html = ""
return u'<option value="{0}"{1}{2}>{3}</option>'.format(
escape(option_value), selected_html, attrs_html,
conditional_escape(force_unicode(option_label))
)
'''
return u'<option value="%s"%s%s>%s</option>' % (
escape(option_value), selected_html, attrs_html,
conditional_escape(force_unicode(option_label)))
'''
# Normalize to strings.
selected_choices = set([force_unicode(v) for v in selected_choices])
output = []
for option_value, option_label, option_attrs in chain(self.choices, choices):
if isinstance(option_label, (list, tuple)):
output.append(u'<optgroup label="%s">' % escape(force_unicode(option_value)))
for option in option_label:
output.append(render_option(*option))
output.append(u'</optgroup>')
else:
output.append(render_option(option_value, option_label,
option_attrs))
return u'\n'.join(output)
class SelectMultiple(forms.SelectMultiple, Select):
pass
Example:
OPTIONS = [
["AUT", "Australia", {'selected':'selected', 'data-index':'1'}],
["DEU", "Germany", {'selected':'selected'}],
["NLD", "Neitherlands", {'selected':'selected'}],
["USA", "United States", {}]
]
回答4:
ModelMultipleChoiceField is your friend. A CharField is capable of storing one selection, but not multiple, without some extra work, which I would recommend against.
API doc for ModelMultipleChoiceField
回答5:
You can also define countries field in your form class as
Countries = forms.MultipleChoiceField(widget=forms.SelectMultiple,
choices=OPTIONS_TUPPLE)
I don't know which one is better in SelectMultiple and CheckboxSelectMultiple but it also works.
For more details you can use django documentation about widgets.
来源：https://stackoverflow.com/questions/15393134/django-how-can-i-create-a-multiple-select-form