Model forms

ModelForm API reference. For introductory material about using a ModelForm, see the Creating forms from models topic guide.

Model form Meta API

class ModelFormOptions[sorgente]

The _meta API is used to build forms that reflect a Django model. It is accessible through the _meta attribute of each model form, and is an django.forms.models.ModelFormOptions instance.

The structure of the generated form can be customized by defining metadata options as attributes of an inner Meta class. For example:

from django.forms import ModelForm
from myapp.models import Book


class BookForm(ModelForm):
    class Meta:
        model = Book
        fields = ["title", "author"]
        help_texts = {
            "title": "The title of the book",
            "author": "The author of the book",
        }
        # ... other attributes

Required attributes are model, and either fields or exclude. All other Meta attributes are optional.

Optional attributes, other than localized_fields and formfield_callback, expect a dictionary that maps a model field name to a value. Any field that is not defined in the dictionary falls back to the field’s default value.

Invalid field names

Invalid or excluded field names in an optional dictionary attribute have no effect, since fields that are not included are not accessed.

Invalid Meta class attributes

You may define any attribute on a Meta class. Typos or incorrect attribute names do not raise an error.

error_messages

ModelFormOptions.error_messages

A dictionary that maps a model field name to a dictionary of error message keys (null, blank, invalid, unique, etc.) mapped to custom error messages.

When a field is not specified, Django will fall back on the error messages defined in that model field’s django.db.models.Field.error_messages and then finally on the default error messages for that field type.

exclude

ModelFormOptions.exclude

A tuple or list of model field names to be excluded from the form.

Either fields or exclude must be set. If neither are set, an ImproperlyConfigured exception will be raised. If exclude is set and fields is unset, all model fields, except for those specified in exclude, are included in the form.

field_classes

ModelFormOptions.field_classes

A dictionary that maps a model field name to a Field class, which overrides the form_class used in the model field’s Field.formfield() method.

When a field is not specified, Django will fall back on the model field’s default field class.

fields

ModelFormOptions.fields

A tuple or list of model field names to be included in the form. The value '__all__' can be used to specify that all fields should be included.

If any field is specified in exclude, this will not be included in the form despite being specified in fields.

Either fields or exclude must be set. If neither are set, an ImproperlyConfigured exception will be raised.

formfield_callback

ModelFormOptions.formfield_callback

A function or callable that takes a model field and returns a django.forms.Field object.

help_texts

ModelFormOptions.help_texts

A dictionary that maps a model field name to a help text string.

When a field is not specified, Django will fall back on that model field’s help_text.

labels

ModelFormOptions.labels

A dictionary that maps a model field names to a label string.

When a field is not specified, Django will fall back on that model field’s verbose_name and then the field’s attribute name.

localized_fields

ModelFormOptions.localized_fields

A tuple or list of model field names to be localized. The value '__all__' can be used to specify that all fields should be localized.

By default, form fields are not localized, see enabling localization of fields for more details.

model

ModelFormOptions.model

Required. The django.db.models.Model to be used for the ModelForm.

widgets

ModelFormOptions.widgets

A dictionary that maps a model field name to a django.forms.Widget.

When a field is not specified, Django will fall back on the default widget for that particular type of django.db.models.Field.

Model form factory functions

modelform_factory

modelform_factory(model, form=ModelForm, fields=None, exclude=None, formfield_callback=None, widgets=None, localized_fields=None, labels=None, help_texts=None, error_messages=None, field_classes=None)[sorgente]

Returns a ModelForm class for the given model. You can optionally pass a form argument to use as a starting point for constructing the ModelForm.

fields is an optional list of field names. If provided, only the named fields will be included in the returned fields.

exclude is an optional list of field names. If provided, the named fields will be excluded from the returned fields, even if they are listed in the fields argument.

formfield_callback is a callable that takes a model field and returns a form field.

widgets is a dictionary of model field names mapped to a widget.

localized_fields is a list of names of fields which should be localized.

labels is a dictionary of model field names mapped to a label.

help_texts is a dictionary of model field names mapped to a help text.

error_messages is a dictionary of model field names mapped to a dictionary of error messages.

field_classes is a dictionary of model field names mapped to a form field class.

See ModelForm factory function for example usage.

You must provide the list of fields explicitly, either via keyword arguments fields or exclude, or the corresponding attributes on the form’s inner Meta class. See Selecting the fields to use for more information. Omitting any definition of the fields to use will result in an ImproperlyConfigured exception.

modelformset_factory

modelformset_factory(model, form=ModelForm, formfield_callback=None, formset=BaseModelFormSet, extra=1, can_delete=False, can_order=False, max_num=None, fields=None, exclude=None, widgets=None, validate_max=False, localized_fields=None, labels=None, help_texts=None, error_messages=None, min_num=None, validate_min=False, field_classes=None, absolute_max=None, can_delete_extra=True, renderer=None, edit_only=False)[sorgente]

Returns a FormSet class for the given model class.

Arguments model, form, fields, exclude, formfield_callback, widgets, localized_fields, labels, help_texts, error_messages, and field_classes are all passed through to modelform_factory().

Arguments formset, extra, can_delete, can_order, max_num, validate_max, min_num, validate_min, absolute_max, can_delete_extra, and renderer are passed through to formset_factory(). See formsets for details.

The edit_only argument allows preventing new objects creation.

See Model formsets for example usage.

inlineformset_factory

inlineformset_factory(parent_model, model, form=ModelForm, formset=BaseInlineFormSet, fk_name=None, fields=None, exclude=None, extra=3, can_order=False, can_delete=True, max_num=None, formfield_callback=None, widgets=None, validate_max=False, localized_fields=None, labels=None, help_texts=None, error_messages=None, min_num=None, validate_min=False, field_classes=None, absolute_max=None, can_delete_extra=True, renderer=None, edit_only=False)[sorgente]

Returns an InlineFormSet using modelformset_factory() with defaults of formset=BaseInlineFormSet, can_delete=True, and extra=3.

If your model has more than one ForeignKey to the parent_model, you must specify a fk_name.

See Inline formsets for example usage.