|| - `allow_delete`_|

|| - `prototype`_|

|| - `prototype_name`_|

|| - `delete_empty`_|

| Inherited| - `label`_|

|| - `label_attr`_|

| options| - `error_bubbling`_|

|| - `error_mapping`_|

|| - `by_reference`_|

|| - `empty_data`_|

|| - `required`_|

|| - `mapped`_|

| Parent type|:doc:`form</reference/forms/types/form>`|

you may want to change the placeholder so that unrelated placeholders are not

replaced with the same value.

delete_empty

**type**: ``Boolean`` **default**: ``false``

If you want to explicitly remove entirely empty collection entries from your

form you have to set this option to true. Existing collection entries will

however only be deleted if you have `allow_delete`_ option enabled, otherwise

the empty values will be kept.

Inherited options

..include::/reference/forms/types/options/empty_data.rst.inc

..include::/reference/forms/types/options/required.rst.inc

..include::/reference/forms/types/options/mapped.rst.inc

The true default value of this option depends on the field options:

* If ``compound`` is ``true`` and ``data_class`` is set, then ``new $data_class()``;

* If ``compound`` is ``true`` and no ``data_class`` is set, then ``array()``;

* If ``compound`` is ``false``, then ``null``.

* If ``required`` is ``true`` and ``data_class`` is set, then ``new $data_class()``;

* If ``required`` is ``true`` and no ``data_class`` is set, then ``array()``;

* If ``required`` is ``false``, then ``null``.

.. tip::

The ``compound`` option is set to ``true`` when the field actually represents

a collection of fields (e.g. a form of fields).

For example, if you want the ``gender`` field to be set to ``null`` when no

value is selected, you can do it like this:

But you can customize this to your needs. For example, if you want the ``gender`` field to be

set to explicitly ``null`` when no value is selected, you can do it like this:

.. code-block:: php

guess your field type, then the value of this option will be guessed from

your validation information.

.. _`HTML5 required attribute`:http://diveintohtml5.info/forms.html

.. _`HTML5 required attribute`: http://diveintohtml5.info/forms.html

.. note::

The required option does also affect the way how empty data of your form is

being handled. For further details check the :doc:` empty_data</reference/forms/types/options/empty_data.rst.inc>` option.