form Field Type¶

The form type predefines a couple of options that are then available on all types for which form is the parent type.

Options	action by_reference cascade_validation compound constraints data data_class empty_data error_bubbling error_mapping extra_fields_message inherit_data invalid_message invalid_message_parameters label_attr mapped max_length method pattern post_max_size_message property_path read_only required trim
Inherited options	attr auto_initialize block_name disabled label translation_domain
Parent	none
Class	`FormType`

Field Options¶

action¶

2.3 新版功能: The action option was introduced in Symfony 2.3.

type: string default: empty string

This option specifies where to send the form’s data on submission (usually a URI). Its value is rendered as the action attribute of the form element. An empty value is considered a same-document reference, i.e. the form will be submitted to the same URI that rendered the form.

by_reference¶

type: Boolean default: true

In most cases, if you have a name field, then you expect setName() to be called on the underlying object. In some cases, however, setName() may not be called. Setting by_reference ensures that the setter is called in all cases.

To explain this further, here’s a simple example:

$builder = $this->createFormBuilder($article);
$builder
    ->add('title', 'text')
    ->add(
        $builder->create('author', 'form', array('by_reference' => ?))
            ->add('name', 'text')
            ->add('email', 'email')
    )

If by_reference is true, the following takes place behind the scenes when you call submit() (or handleRequest()) on the form:

$article->setTitle('...');
$article->getAuthor()->setName('...');
$article->getAuthor()->setEmail('...');

Notice that setAuthor() is not called. The author is modified by reference.

If you set by_reference to false, submitting looks like this:

$article->setTitle('...');
$author = $article->getAuthor();
$author->setName('...');
$author->setEmail('...');
$article->setAuthor($author);

So, all that by_reference=false really does is force the framework to call the setter on the parent object.

Similarly, if you’re using the collection form type where your underlying collection data is an object (like with Doctrine’s ArrayCollection), then by_reference must be set to false if you need the adder and remover (e.g. addAuthor() and removeAuthor()) to be called.

cascade_validation¶

type: Boolean default: false

Set this option to true to force validation on embedded form types. For example, if you have a ProductType with an embedded CategoryType, setting cascade_validation to true on ProductType will cause the data from CategoryType to also be validated.

小技巧

Instead of using this option, it is recommended that you use the Valid constraint in your model to force validation on a child object stored on a property. This cascades only the validation but not the use of the validation_group option on child forms. You can read more about this in the section about Embedding a Single Object.

小技巧

By default the error_bubbling option is enabled for the collection Field Type, which passes the errors to the parent form. If you want to attach the errors to the locations where they actually occur you have to set error_bubbling to false.

compound¶

type: boolean default: true

This option specifies if a form is compound. This is independent of whether the form actually has children. A form can be compound but not have any children at all (e.g. an empty collection form).

constraints¶

type: array or Constraint default: null

Allows you to attach one or more validation constraints to a specific field. For more information, see Adding Validation. This option is added in the FormTypeValidatorExtension form extension.

data¶

type: mixed default: Defaults to field of the underlying object (if there is one)

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

$builder->add('token', 'hidden', array(
    'data' => 'abcdef',
));

注解

The default values for form fields are taken directly from the underlying data structure (e.g. an entity or an array). The data option overrides this default value.

data_class¶

type: string

This option is used to set the appropriate data mapper to be used by the form, so you can use it for any form field type which requires an object.

$builder->add('media', 'sonata_media_type', array(
    'data_class' => 'Acme\DemoBundle\Entity\Media',
));

empty_data¶

type: mixed

The actual default value of this option depends on other field options:

If data_class is set and required is true, then new $data_class();
If data_class is set and required is false, then null;
If data_class is not set and compound is true, then array() (empty array);
If data_class is not set and compound is false, then '' (empty string).

This option determines what value the field will return when the submitted value is empty.

But you can customize this to your needs. For example, if you want the gender choice field to be explicitly set to null when no value is selected, you can do it like this:

$builder->add('gender', 'choice', array(
    'choices' => array(
        'm' => 'Male',
        'f' => 'Female'
    ),
    'required'    => false,
    'empty_value' => 'Choose your gender',
    'empty_data'  => null
));

注解

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

error_bubbling¶

type: Boolean default: false unless the form is compound

If true, any errors for this field will be passed to the parent field or form. For example, if set to true on a normal field, any errors for that field will be attached to the main form, not to the specific field.

error_mapping¶

2.1 新版功能: The error_mapping option was introduced in Symfony 2.1.

type: array default: empty

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 setDefaultOptions(OptionsResolverInterface $resolver)
{
    $resolver->setDefaults(array(
        'error_mapping' => array(
            '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 simply 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 left side of the error mapping also accepts a dot ., which refers to the field itself. That means that any error added to the field is added to the given nested field instead;
The right side contains simply the names of fields in the form.

extra_fields_message¶

type: string default: This form should not contain extra fields.

This is the validation error message that’s used if the submitted form data contains one or more fields that are not part of the form definition. The placeholder {{ extra_fields }} can be used to display a comma separated list of the submitted extra field names.

inherit_data¶

2.3 新版功能: The inherit_data option was introduced in Symfony 2.3. Before, it was known as virtual.

type: boolean default: false

This option determines if the form will inherit data from its parent form. This can be useful if you have a set of fields that are duplicated across multiple forms. See How to Reduce Code Duplication with “inherit_data”.

invalid_message¶

type: string default: This value is not valid

This is the validation error message that’s used if the data entered into this field doesn’t make sense (i.e. fails validation).

This might happen, for example, if the user enters a nonsense string into a time field that cannot be converted into a real time or if the user enters a string (e.g. apple) into a number field.

Normal (business logic) validation (such as when setting a minimum length for a field) should be set using validation messages with your validation rules (reference).

invalid_message_parameters¶

type: array default: array()

When setting the invalid_message option, you may need to include some variables in the string. This can be done by adding placeholders to that option and including the variables in this option:

$builder->add('some_field', 'some_type', array(
    // ...
    'invalid_message'            => 'You entered an invalid value - it should include %num% letters',
    'invalid_message_parameters' => array('%num%' => 6),
));

label_attr¶

type: array default: array()

Sets the HTML attributes for the <label> element, which will be used when rendering the label for the field. It’s an associative array with HTML attribute as a key. This attributes can also be directly set inside the template:

Twig

{{ form_label(form.name, 'Your name', {'label_attr': {'class': 'CUSTOM_LABEL_CLASS'}}) }}

PHP

echo $view['form']->label(
    $form['name'],
    'Your name',
    array('label_attr' => array('class' => 'CUSTOM_LABEL_CLASS'))
);

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.

max_length¶

type: integer default: null

If this option is not null, an attribute maxlength is added, which is used by some browsers to limit the amount of text in a field.

This is just a browser validation, so data must still be validated server-side.

method¶

2.3 新版功能: The method option was introduced in Symfony 2.3.

type: string default: POST

This option specifies the HTTP method used to submit the form’s data. Its value is rendered as the method attribute of the form element and is used to decide whether to process the form submission in the handleRequest() method after submission. Possible values are:

POST
GET
PUT
DELETE
PATCH

注解

When the method is PUT, PATCH, or DELETE, Symfony will automatically render a _method hidden field in your form. This is used to “fake” these HTTP methods, as they’re not supported on standard browsers. For more information, see How to Use HTTP Methods beyond GET and POST in Routes.

注解

The PATCH method allows submitting partial data. In other words, if the submitted form data is missing certain fields, those will be ignored and the default values (if any) will be used. With all other HTTP methods, if the submitted form data is missing some fields, those fields are set to null.

pattern¶

type: string default: null

This adds an HTML5 pattern attribute to restrict the field input by a given regular expression.

警告

The pattern attribute provides client-side validation for convenience purposes only and must not be used as a replacement for reliable server-side validation.

注解

When using validation constraints, this option is set automatically for some constraints to match the server-side validation.

post_max_size_message¶

type: string default: The uploaded file was too large. Please try to upload a smaller file.

This is the validation error message that’s used if submitted POST form data exceeds php.ini‘s post_max_size directive. The {{ max }} placeholder can be used to display the allowed size.

注解

Validating the post_max_size only happens on the root form.

property_path¶

type: any default: the field's name

Fields display a property value of the form’s domain object by default. When the form is submitted, the submitted value is written back into the object.

If you want to override the property that a field reads from and writes to, you can set the property_path option. Its default value is the field’s name.

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.

2.1 新版功能: The mapped option was introduced in Symfony 2.1 for this use-case.

read_only¶

type: Boolean default: false

If this option is true, the field will be rendered with the readonly attribute so that the field is not editable.

required¶

type: Boolean default: true

If true, an HTML5 required attribute will be rendered. The corresponding label will also render with a required class.

This is superficial and independent from validation. At best, if you let Symfony guess your field type, then the value of this option will be guessed from your validation information.

注解

The required option also affects how empty data for each field is handled. For more details, see the empty_data option.

trim¶

type: Boolean default: true

If true, the whitespace of the submitted string value will be stripped via the trim() function when the data is bound. This guarantees that if a value is submitted with extra whitespace, it will be removed before the value is merged back onto the underlying object.

Inherited Options¶

The following options are defined in the BaseType class. The BaseType class is the parent class for both the form type and the button type, but it is not part of the form type tree (i.e. it can not be used as a form type on its own).

attr¶

type: array default: Empty array

If you want to add extra attributes to an HTML field representation you can use the attr option. It’s an associative array with HTML attributes as keys. This can be useful when you need to set a custom class for some widget:

$builder->add('body', 'textarea', array(
    'attr' => array('class' => 'tinymce'),
));

auto_initialize¶

type: boolean default: true

An internal option: sets whether the form should be initialized automatically. For all fields, this option should only be true for root forms. You won’t need to change this option and probably won’t need to worry about it.

block_name¶

type: string default: the form’s name (see Knowing which block to customize)

Allows you to override the block name used to render the form type. Useful for example if you have multiple instances of the same form and you need to personalize the rendering of the forms individually.

disabled¶

2.1 新版功能: The disabled option was introduced in Symfony 2.1.

type: boolean default: false

If you don’t want a user to modify the value of a field, you can set the disabled option to true. Any submitted value will be ignored.

label¶

type: string default: The label is “guessed” from the field name

Sets the label that will be used when rendering the field. Setting to false will suppress the label. The label can also be directly set inside the template:

Twig

{{ form_label(form.name, 'Your name') }}

PHP

echo $view['form']->label(
    $form['name'],
    'Your name'
);

translation_domain¶

type: string default: messages

This is the translation domain that will be used for any labels or options that are rendered for this field.