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HiddenType Field

HiddenType Field

The hidden type represents a hidden input field.

Rendered as input hidden field
Overridden options
Inherited options
Parent type FormType
Class Symfony\Component\Form\Extension\Core\Type\HiddenType

Overridden Options

compound

type: boolean default: false

This option specifies whether the type contains child types or not. This option is managed internally for built-in types, so there is no need to configure it explicitly.

error_bubbling

default: true

Pass errors to the root form, otherwise they will not be visible.

required

default: false

Hidden fields cannot have a required attribute.

Inherited Options

These options inherit from the FormType:

data

type: mixed default: Defaults to field of the underlying structure.

When you create a form, each field initially displays the value of the corresponding property of the form’s domain data (e.g. if you bind an object to the form). If you want to override this initial value for the form or an individual field, you can set it in the data option:

use Symfony\Component\Form\Extension\Core\Type\HiddenType;
// ...

$builder->add('token', HiddenType::class, [
    'data' => 'abcdef',
]);

Caution

The data option always overrides the value taken from the domain data (object) when rendering. This means the object value is also overridden when the form edits an already persisted object, causing it to lose its persisted value when the form is submitted.

empty_data

type: mixed

The default value is '' (the empty string).

This option determines what value the field will return when the submitted value is empty (or missing). It does not set an initial value if none is provided when the form is rendered in a view.

This means it helps you handling form submission with blank fields. For example, if you want the name field to be explicitly set to John Doe when no value is selected, you can do it like this:

$builder->add('name', null, [
    'required'   => false,
    'empty_data' => 'John Doe',
]);

This will still render an empty text box, but upon submission the John Doe value will be set. Use the data or placeholder options to show this initial value in the rendered form.

If a form is compound, you can set empty_data as an array, object or closure. See the How to Configure empty Data for a Form Class article for more details about these options.

Note

If you want to set the empty_data option for your entire form class, see the How to Configure empty Data for a Form Class article.

Caution

Form data transformers will still be applied to the empty_data value. This means that an empty string will be cast to null. Use a custom data transformer if you explicitly want to return the empty string.

error_mapping

type: array default: []

This option allows you to modify the target of a validation error.

Imagine you have a custom method named matchingCityAndZipCode() that validates whether the city and zip code match. Unfortunately, there is no matchingCityAndZipCode field in your form, so all that Symfony can do is display the error on top of the form.

With customized error mapping, you can do better: map the error to the city field so that it displays above it:

public function configureOptions(OptionsResolver $resolver)
{
    $resolver->setDefaults([
        'error_mapping' => [
            'matchingCityAndZipCode' => 'city',
        ],
    ]);
}

Here are the rules for the left and the right side of the mapping:

  • The left side contains property paths;
  • If the violation is generated on a property or method of a class, its path is the propertyName;
  • If the violation is generated on an entry of an array or ArrayAccess object, the property path is [indexName];
  • You can construct nested property paths by concatenating them, separating properties by dots. For example: addresses[work].matchingCityAndZipCode;
  • The right side contains the names of fields in the form.

By default, errors for any property that is not mapped will bubble up to the parent form. You can use the dot (.) on the left side to map errors of all unmapped properties to a particular field. For instance, to map all these errors to the city field, use:

$resolver->setDefaults([
    'error_mapping' => [
        '.' => 'city',
    ],
]);

mapped

type: boolean default: true

If you wish the field to be ignored when reading or writing to the object, you can set the mapped option to false.

property_path

type: any default: the field's name

By default form fields read from and write to the properties with the same names in the form’s domain object. The property_path option lets you define which property a field reads from and writes to. The value of this option can be any valid PropertyAccess syntax.

If you wish the field to be ignored when reading or writing to the object you can set the property_path option to false, but using property_path for this purpose is deprecated, you should use the mapped option.

This work, including the code samples, is licensed under a Creative Commons BY-SA 3.0 license.