=========== Form fields =========== .. module:: django.forms.fields :synopsis: Django's built-in form fields. .. currentmodule:: django.forms .. class:: Field(**kwargs) When you create a ``Form`` class, the most important part is defining the fields of the form. Each field has custom validation logic, along with a few other hooks. .. method:: Field.clean(value) Although the primary way you'll use ``Field`` classes is in ``Form`` classes, you can also instantiate them and use them directly to get a better idea of how they work. Each ``Field`` instance has a ``clean()`` method, which takes a single argument and either raises a ``django.forms.ValidationError`` exception or returns the clean value:: >>> from django import forms >>> f = forms.EmailField() >>> f.clean('foo@example.com') u'foo@example.com' >>> f.clean(u'foo@example.com') u'foo@example.com' >>> f.clean('invalid e-mail address') Traceback (most recent call last): ... ValidationError: [u'Enter a valid e-mail address.'] Core field arguments -------------------- Each ``Field`` class constructor takes at least these arguments. Some ``Field`` classes take additional, field-specific arguments, but the following should *always* be accepted: ``required`` ~~~~~~~~~~~~ .. attribute:: Field.required By default, each ``Field`` class assumes the value is required, so if you pass an empty value -- either ``None`` or the empty string (``""``) -- then ``clean()`` will raise a ``ValidationError`` exception:: >>> f = forms.CharField() >>> f.clean('foo') u'foo' >>> f.clean('') Traceback (most recent call last): ... ValidationError: [u'This field is required.'] >>> f.clean(None) Traceback (most recent call last): ... ValidationError: [u'This field is required.'] >>> f.clean(' ') u' ' >>> f.clean(0) u'0' >>> f.clean(True) u'True' >>> f.clean(False) u'False' To specify that a field is *not* required, pass ``required=False`` to the ``Field`` constructor:: >>> f = forms.CharField(required=False) >>> f.clean('foo') u'foo' >>> f.clean('') u'' >>> f.clean(None) u'' >>> f.clean(0) u'0' >>> f.clean(True) u'True' >>> f.clean(False) u'False' If a ``Field`` has ``required=False`` and you pass ``clean()`` an empty value, then ``clean()`` will return a *normalized* empty value rather than raising ``ValidationError``. For ``CharField``, this will be a Unicode empty string. For other ``Field`` classes, it might be ``None``. (This varies from field to field.) ``label`` ~~~~~~~~~ .. attribute:: Field.label The ``label`` argument lets you specify the "human-friendly" label for this field. This is used when the ``Field`` is displayed in a ``Form``. As explained in "Outputting forms as HTML" above, the default label for a ``Field`` is generated from the field name by converting all underscores to spaces and upper-casing the first letter. Specify ``label`` if that default behavior doesn't result in an adequate label. Here's a full example ``Form`` that implements ``label`` for two of its fields. We've specified ``auto_id=False`` to simplify the output:: >>> class CommentForm(forms.Form): ... name = forms.CharField(label='Your name') ... url = forms.URLField(label='Your Web site', required=False) ... comment = forms.CharField() >>> f = CommentForm(auto_id=False) >>> print f Your name: Your Web site: Comment: ``initial`` ~~~~~~~~~~~ .. attribute:: Field.initial The ``initial`` argument lets you specify the initial value to use when rendering this ``Field`` in an unbound ``Form``. To specify dynamic initial data, see the :attr:`Form.initial` parameter. The use-case for this is when you want to display an "empty" form in which a field is initialized to a particular value. For example:: >>> class CommentForm(forms.Form): ... name = forms.CharField(initial='Your name') ... url = forms.URLField(initial='http://') ... comment = forms.CharField() >>> f = CommentForm(auto_id=False) >>> print f Name: Url: Comment: You may be thinking, why not just pass a dictionary of the initial values as data when displaying the form? Well, if you do that, you'll trigger validation, and the HTML output will include any validation errors:: >>> class CommentForm(forms.Form): ... name = forms.CharField() ... url = forms.URLField() ... comment = forms.CharField() >>> default_data = {'name': 'Your name', 'url': 'http://'} >>> f = CommentForm(default_data, auto_id=False) >>> print f Name: Url: Comment: This is why ``initial`` values are only displayed for unbound forms. For bound forms, the HTML output will use the bound data. Also note that ``initial`` values are *not* used as "fallback" data in validation if a particular field's value is not given. ``initial`` values are *only* intended for initial form display:: >>> class CommentForm(forms.Form): ... name = forms.CharField(initial='Your name') ... url = forms.URLField(initial='http://') ... comment = forms.CharField() >>> data = {'name': '', 'url': '', 'comment': 'Foo'} >>> f = CommentForm(data) >>> f.is_valid() False # The form does *not* fall back to using the initial values. >>> f.errors {'url': [u'This field is required.'], 'name': [u'This field is required.']} Instead of a constant, you can also pass any callable:: >>> import datetime >>> class DateForm(forms.Form): ... day = forms.DateField(initial=datetime.date.today) >>> print DateForm() Day: The callable will be evaluated only when the unbound form is displayed, not when it is defined. ``widget`` ~~~~~~~~~~ .. attribute:: Field.widget The ``widget`` argument lets you specify a ``Widget`` class to use when rendering this ``Field``. See :doc:`/ref/forms/widgets` for more information. ``help_text`` ~~~~~~~~~~~~~ .. attribute:: Field.help_text The ``help_text`` argument lets you specify descriptive text for this ``Field``. If you provide ``help_text``, it will be displayed next to the ``Field`` when the ``Field`` is rendered by one of the convenience ``Form`` methods (e.g., ``as_ul()``). Here's a full example ``Form`` that implements ``help_text`` for two of its fields. We've specified ``auto_id=False`` to simplify the output:: >>> class HelpTextContactForm(forms.Form): ... subject = forms.CharField(max_length=100, help_text='100 characters max.') ... message = forms.CharField() ... sender = forms.EmailField(help_text='A valid e-mail address, please.') ... cc_myself = forms.BooleanField(required=False) >>> f = HelpTextContactForm(auto_id=False) >>> print f.as_table() Subject:
100 characters max. Message: Sender:
A valid e-mail address, please. Cc myself: >>> print f.as_ul()
  • Subject: 100 characters max.
  • Message:
  • Sender: A valid e-mail address, please.
  • Cc myself:
    • >>> print f.as_p()

    Subject: 100 characters max.

    Message:

    Sender: A valid e-mail address, please.

    Cc myself:

    ``error_messages`` ~~~~~~~~~~~~~~~~~~ .. versionadded:: 1.0 .. attribute:: Field.error_messages The ``error_messages`` argument lets you override the default messages that the field will raise. Pass in a dictionary with keys matching the error messages you want to override. For example, here is the default error message:: >>> generic = forms.CharField() >>> generic.clean('') Traceback (most recent call last): ... ValidationError: [u'This field is required.'] And here is a custom error message:: >>> name = forms.CharField(error_messages={'required': 'Please enter your name'}) >>> name.clean('') Traceback (most recent call last): ... ValidationError: [u'Please enter your name'] In the `built-in Field classes`_ section below, each ``Field`` defines the error message keys it uses. ``validators`` ~~~~~~~~~~~~~~ .. versionadded:: 1.2 .. attribute:: Field.validators The ``validators`` argument lets you provide a list of validation functions for this field. See the :doc:`validators documentation ` for more information. ``localize`` ~~~~~~~~~~~~ .. versionadded:: 1.2 .. attribute:: Field.localize The ``localize`` argument enables the localization of form data, input as well as the rendered output. See the :ref:`format localization ` documentation for more information. Built-in ``Field`` classes -------------------------- Naturally, the ``forms`` library comes with a set of ``Field`` classes that represent common validation needs. This section documents each built-in field. For each field, we describe the default widget used if you don't specify ``widget``. We also specify the value returned when you provide an empty value (see the section on ``required`` above to understand what that means). ``BooleanField`` ~~~~~~~~~~~~~~~~ .. class:: BooleanField(**kwargs) * Default widget: ``CheckboxInput`` * Empty value: ``False`` * Normalizes to: A Python ``True`` or ``False`` value. * Validates that the value is ``True`` (e.g. the check box is checked) if the field has ``required=True``. * Error message keys: ``required`` .. versionchanged:: 1.0 The empty value for a ``CheckboxInput`` (and hence the standard ``BooleanField``) has changed to return ``False`` instead of ``None`` in the Django 1.0. .. note:: Since all ``Field`` subclasses have ``required=True`` by default, the validation condition here is important. If you want to include a boolean in your form that can be either ``True`` or ``False`` (e.g. a checked or unchecked checkbox), you must remember to pass in ``required=False`` when creating the ``BooleanField``. ``CharField`` ~~~~~~~~~~~~~ .. class:: CharField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates ``max_length`` or ``min_length``, if they are provided. Otherwise, all inputs are valid. * Error message keys: ``required``, ``max_length``, ``min_length`` Has two optional arguments for validation: .. attribute:: CharField.max_length .. attribute:: CharField.min_length If provided, these arguments ensure that the string is at most or at least the given length. ``ChoiceField`` ~~~~~~~~~~~~~~~ .. class:: ChoiceField(**kwargs) * Default widget: ``Select`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates that the given value exists in the list of choices. * Error message keys: ``required``, ``invalid_choice`` Takes one extra required argument: .. attribute:: ChoiceField.choices An iterable (e.g., a list or tuple) of 2-tuples to use as choices for this field. This argument accepts the same formats as the ``choices`` argument to a model field. See the :ref:`model field reference documentation on choices ` for more details. ``TypedChoiceField`` ~~~~~~~~~~~~~~~~~~~~ .. class:: TypedChoiceField(**kwargs) Just like a :class:`ChoiceField`, except :class:`TypedChoiceField` takes two extra arguments, ``coerce`` and ``empty_value``. * Default widget: ``Select`` * Empty value: Whatever you've given as ``empty_value`` * Normalizes to: A value of the type provided by the ``coerce`` argument. * Validates that the given value exists in the list of choices and can be coerced. * Error message keys: ``required``, ``invalid_choice`` Takes extra arguments: .. attribute:: TypedChoiceField.coerce A function that takes one argument and returns a coerced value. Examples include the built-in ``int``, ``float``, ``bool`` and other types. Defaults to an identity function. .. attribute:: TypedChoiceField.empty_value The value to use to represent "empty." Defaults to the empty string; ``None`` is another common choice here. ``DateField`` ~~~~~~~~~~~~~ .. class:: DateField(**kwargs) * Default widget: ``DateInput`` * Empty value: ``None`` * Normalizes to: A Python ``datetime.date`` object. * Validates that the given value is either a ``datetime.date``, ``datetime.datetime`` or string formatted in a particular date format. * Error message keys: ``required``, ``invalid`` Takes one optional argument: .. attribute:: DateField.input_formats A list of formats used to attempt to convert a string to a valid ``datetime.date`` object. If no ``input_formats`` argument is provided, the default input formats are:: '%Y-%m-%d', '%m/%d/%Y', '%m/%d/%y', # '2006-10-25', '10/25/2006', '10/25/06' '%b %d %Y', '%b %d, %Y', # 'Oct 25 2006', 'Oct 25, 2006' '%d %b %Y', '%d %b, %Y', # '25 Oct 2006', '25 Oct, 2006' '%B %d %Y', '%B %d, %Y', # 'October 25 2006', 'October 25, 2006' '%d %B %Y', '%d %B, %Y', # '25 October 2006', '25 October, 2006' .. versionchanged:: 1.1 The ``DateField`` previously used a ``TextInput`` widget by default. It now uses a ``DateInput`` widget. ``DateTimeField`` ~~~~~~~~~~~~~~~~~ .. class:: DateTimeField(**kwargs) * Default widget: ``DateTimeInput`` * Empty value: ``None`` * Normalizes to: A Python ``datetime.datetime`` object. * Validates that the given value is either a ``datetime.datetime``, ``datetime.date`` or string formatted in a particular datetime format. * Error message keys: ``required``, ``invalid`` Takes one optional argument: .. attribute:: DateTimeField.input_formats A list of formats used to attempt to convert a string to a valid ``datetime.datetime`` object. If no ``input_formats`` argument is provided, the default input formats are:: '%Y-%m-%d %H:%M:%S', # '2006-10-25 14:30:59' '%Y-%m-%d %H:%M', # '2006-10-25 14:30' '%Y-%m-%d', # '2006-10-25' '%m/%d/%Y %H:%M:%S', # '10/25/2006 14:30:59' '%m/%d/%Y %H:%M', # '10/25/2006 14:30' '%m/%d/%Y', # '10/25/2006' '%m/%d/%y %H:%M:%S', # '10/25/06 14:30:59' '%m/%d/%y %H:%M', # '10/25/06 14:30' '%m/%d/%y', # '10/25/06' .. versionchanged:: 1.0 The ``DateTimeField`` used to use a ``TextInput`` widget by default. This has now changed. ``DecimalField`` ~~~~~~~~~~~~~~~~ .. versionadded:: 1.0 .. class:: DecimalField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``None`` * Normalizes to: A Python ``decimal``. * Validates that the given value is a decimal. Leading and trailing whitespace is ignored. * Error message keys: ``required``, ``invalid``, ``max_value``, ``min_value``, ``max_digits``, ``max_decimal_places``, ``max_whole_digits`` Takes four optional arguments: .. attribute:: DecimalField.max_value .. attribute:: DecimalField.min_value These attributes define the limits for the fields value. .. attribute:: DecimalField.max_digits The maximum number of digits (those before the decimal point plus those after the decimal point, with leading zeros stripped) permitted in the value. .. attribute:: DecimalField.decimal_places The maximum number of decimal places permitted. ``EmailField`` ~~~~~~~~~~~~~~ .. class:: EmailField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates that the given value is a valid e-mail address, using a moderately complex regular expression. * Error message keys: ``required``, ``invalid`` Has two optional arguments for validation, ``max_length`` and ``min_length``. If provided, these arguments ensure that the string is at most or at least the given length. .. versionchanged:: 1.2 The EmailField previously did not recognize e-mail addresses as valid that contained an IDN (Internationalized Domain Name; a domain containing unicode characters) domain part. This has now been corrected. ``FileField`` ~~~~~~~~~~~~~ .. versionadded:: 1.0 .. class:: FileField(**kwargs) * Default widget: ``ClearableFileInput`` * Empty value: ``None`` * Normalizes to: An ``UploadedFile`` object that wraps the file content and file name into a single object. * Validates that non-empty file data has been bound to the form. * Error message keys: ``required``, ``invalid``, ``missing``, ``empty`` To learn more about the ``UploadedFile`` object, see the :doc:`file uploads documentation `. When you use a ``FileField`` in a form, you must also remember to :ref:`bind the file data to the form `. ``FilePathField`` ~~~~~~~~~~~~~~~~~ .. versionadded:: 1.0 .. class:: FilePathField(**kwargs) * Default widget: ``Select`` * Empty value: ``None`` * Normalizes to: A unicode object * Validates that the selected choice exists in the list of choices. * Error message keys: ``required``, ``invalid_choice`` The field allows choosing from files inside a certain directory. It takes three extra arguments; only ``path`` is required: .. attribute:: FilePathField.path The absolute path to the directory whose contents you want listed. This directory must exist. .. attribute:: FilePathField.recursive If ``False`` (the default) only the direct contents of ``path`` will be offered as choices. If ``True``, the directory will be descended into recursively and all descendants will be listed as choices. .. attribute:: FilePathField.match A regular expression pattern; only files with names matching this expression will be allowed as choices. ``FloatField`` ~~~~~~~~~~~~~~ * Default widget: ``TextInput`` * Empty value: ``None`` * Normalizes to: A Python float. * Validates that the given value is an float. Leading and trailing whitespace is allowed, as in Python's ``float()`` function. * Error message keys: ``required``, ``invalid``, ``max_value``, ``min_value`` Takes two optional arguments for validation, ``max_value`` and ``min_value``. These control the range of values permitted in the field. ``ImageField`` ~~~~~~~~~~~~~~ .. versionadded:: 1.0 .. class:: ImageField(**kwargs) * Default widget: ``ClearableFileInput`` * Empty value: ``None`` * Normalizes to: An ``UploadedFile`` object that wraps the file content and file name into a single object. * Validates that file data has been bound to the form, and that the file is of an image format understood by PIL. * Error message keys: ``required``, ``invalid``, ``missing``, ``empty``, ``invalid_image`` Using an ImageField requires that the `Python Imaging Library`_ is installed. When you use an ``ImageField`` on a form, you must also remember to :ref:`bind the file data to the form `. .. _Python Imaging Library: http://www.pythonware.com/products/pil/ ``IntegerField`` ~~~~~~~~~~~~~~~~ .. class:: IntegerField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``None`` * Normalizes to: A Python integer or long integer. * Validates that the given value is an integer. Leading and trailing whitespace is allowed, as in Python's ``int()`` function. * Error message keys: ``required``, ``invalid``, ``max_value``, ``min_value`` Takes two optional arguments for validation: .. attribute:: IntegerField.max_value .. attribute:: IntegerField.min_value These control the range of values permitted in the field. ``IPAddressField`` ~~~~~~~~~~~~~~~~~~ .. class:: IPAddressField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates that the given value is a valid IPv4 address, using a regular expression. * Error message keys: ``required``, ``invalid`` ``MultipleChoiceField`` ~~~~~~~~~~~~~~~~~~~~~~~ .. class:: MultipleChoiceField(**kwargs) * Default widget: ``SelectMultiple`` * Empty value: ``[]`` (an empty list) * Normalizes to: A list of Unicode objects. * Validates that every value in the given list of values exists in the list of choices. * Error message keys: ``required``, ``invalid_choice``, ``invalid_list`` Takes one extra required argument, ``choices``, as for ``ChoiceField``. ``TypedMultipleChoiceField`` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .. class:: TypedMultipleChoiceField(**kwargs) Just like a :class:`MultipleChoiceField`, except :class:`TypedMultipleChoiceField` takes two extra arguments, ``coerce`` and ``empty_value``. * Default widget: ``SelectMultiple`` * Empty value: Whatever you've given as ``empty_value`` * Normalizes to: A list of values of the type provided by the ``coerce`` argument. * Validates that the given values exists in the list of choices and can be coerced. * Error message keys: ``required``, ``invalid_choice`` Takes two extra arguments, ``coerce`` and ``empty_value``, as for ``TypedChoiceField``. ``NullBooleanField`` ~~~~~~~~~~~~~~~~~~~~ .. class:: NullBooleanField(**kwargs) * Default widget: ``NullBooleanSelect`` * Empty value: ``None`` * Normalizes to: A Python ``True``, ``False`` or ``None`` value. * Validates nothing (i.e., it never raises a ``ValidationError``). ``RegexField`` ~~~~~~~~~~~~~~ .. class:: RegexField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates that the given value matches against a certain regular expression. * Error message keys: ``required``, ``invalid`` Takes one required argument: .. attribute:: RegexField.regex A regular expression specified either as a string or a compiled regular expression object. Also takes ``max_length`` and ``min_length``, which work just as they do for ``CharField``. The optional argument ``error_message`` is also accepted for backwards compatibility. The preferred way to provide an error message is to use the ``error_messages`` argument, passing a dictionary with ``'invalid'`` as a key and the error message as the value. ``SlugField`` ~~~~~~~~~~~~~ .. class:: SlugField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates that the given value contains only letters, numbers, underscores, and hyphens. * Error messages: ``required``, ``invalid`` This field is intended for use in representing a model :class:`~django.db.models.SlugField` in forms. ``TimeField`` ~~~~~~~~~~~~~ .. class:: TimeField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``None`` * Normalizes to: A Python ``datetime.time`` object. * Validates that the given value is either a ``datetime.time`` or string formatted in a particular time format. * Error message keys: ``required``, ``invalid`` Takes one optional argument: .. attribute:: TimeField.input_formats A list of formats used to attempt to convert a string to a valid ``datetime.time`` object. If no ``input_formats`` argument is provided, the default input formats are:: '%H:%M:%S', # '14:30:59' '%H:%M', # '14:30' ``URLField`` ~~~~~~~~~~~~ .. class:: URLField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates that the given value is a valid URL. * Error message keys: ``required``, ``invalid``, ``invalid_link`` Takes the following optional arguments: .. attribute:: URLField.max_length .. attribute:: URLField.min_length Same as ``CharField.max_length`` and ``CharField.min_length``. .. attribute:: URLField.verify_exists If ``True``, the validator will attempt to load the given URL, raising ``ValidationError`` if the page gives a 404. Defaults to ``False``. .. attribute:: URLField.validator_user_agent String used as the user-agent used when checking for a URL's existence. Defaults to the value of the ``URL_VALIDATOR_USER_AGENT`` setting. .. versionchanged:: 1.2 The URLField previously did not recognize URLs as valid that contained an IDN (Internationalized Domain Name; a domain name containing unicode characters) domain name. This has now been corrected. Slightly complex built-in ``Field`` classes ------------------------------------------- ``ComboField`` ~~~~~~~~~~~~~~ .. class:: ComboField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: A Unicode object. * Validates that the given value against each of the fields specified as an argument to the ``ComboField``. * Error message keys: ``required``, ``invalid`` Takes one extra required argument: .. attribute:: ComboField.fields The list of fields that should be used to validate the field's value (in the order in which they are provided). >>> f = ComboField(fields=[CharField(max_length=20), EmailField()]) >>> f.clean('test@example.com') u'test@example.com' >>> f.clean('longemailaddress@example.com') Traceback (most recent call last): ... ValidationError: [u'Ensure this value has at most 20 characters (it has 28).'] ``MultiValueField`` ~~~~~~~~~~~~~~~~~~~ .. class:: MultiValueField(**kwargs) * Default widget: ``TextInput`` * Empty value: ``''`` (an empty string) * Normalizes to: the type returned by the ``compress`` method of the subclass. * Validates that the given value against each of the fields specified as an argument to the ``MultiValueField``. * Error message keys: ``required``, ``invalid`` This abstract field (must be subclassed) aggregates the logic of multiple fields. Subclasses should not have to implement clean(). Instead, they must implement compress(), which takes a list of valid values and returns a "compressed" version of those values -- a single value. For example, :class:`SplitDateTimeField` is a subclass which combines a time field and a date field into a datetime object. Takes one extra required argument: .. attribute:: MultiValueField.fields A list of fields which are cleaned into a single field. Each value in ``clean`` is cleaned by the corresponding field in ``fields`` -- the first value is cleaned by the first field, the second value is cleaned by the second field, etc. Once all fields are cleaned, the list of clean values is "compressed" into a single value. ``SplitDateTimeField`` ~~~~~~~~~~~~~~~~~~~~~~ .. class:: SplitDateTimeField(**kwargs) * Default widget: ``SplitDateTimeWidget`` * Empty value: ``None`` * Normalizes to: A Python ``datetime.datetime`` object. * Validates that the given value is a ``datetime.datetime`` or string formatted in a particular datetime format. * Error message keys: ``required``, ``invalid`` Takes two optional arguments: .. attribute:: SplitDateTimeField.input_date_formats A list of formats used to attempt to convert a string to a valid ``datetime.date`` object. If no ``input_date_formats`` argument is provided, the default input formats for ``DateField`` are used. .. attribute:: SplitDateTimeField.input_time_formats A list of formats used to attempt to convert a string to a valid ``datetime.time`` object. If no ``input_time_formats`` argument is provided, the default input formats for ``TimeField`` are used. .. versionchanged:: 1.1 The ``SplitDateTimeField`` previously used two ``TextInput`` widgets by default. The ``input_date_formats`` and ``input_time_formats`` arguments are also new. Fields which handle relationships --------------------------------- Two fields are available for representing relationships between models: :class:`ModelChoiceField` and :class:`ModelMultipleChoiceField`. Both of these fields require a single ``queryset`` parameter that is used to create the choices for the field. Upon form validation, these fields will place either one model object (in the case of ``ModelChoiceField``) or multiple model objects (in the case of ``ModelMultipleChoiceField``) into the ``cleaned_data`` dictionary of the form. ``ModelChoiceField`` ~~~~~~~~~~~~~~~~~~~~ .. class:: ModelChoiceField(**kwargs) * Default widget: ``Select`` * Empty value: ``None`` * Normalizes to: A model instance. * Validates that the given id exists in the queryset. * Error message keys: ``required``, ``invalid_choice`` Allows the selection of a single model object, suitable for representing a foreign key. A single argument is required: .. attribute:: ModelChoiceField.queryset A ``QuerySet`` of model objects from which the choices for the field will be derived, and which will be used to validate the user's selection. ``ModelChoiceField`` also takes one optional argument: .. attribute:: ModelChoiceField.empty_label By default the ``