api/symfony/Component/Form/DataTransformerInterface.yaml

name: DataTransformerInterface
class_comment: null
dependencies:
- name: TransformationFailedException
  type: class
  source: Symfony\Component\Form\Exception\TransformationFailedException
properties: []
methods:
- name: transform
  visibility: public
  parameters:
  - name: value
  comment: '# * Transforms a value between different representations.

    # *

    # * @author Bernhard Schussek <bschussek@gmail.com>

    # *

    # * @template TValue

    # * @template TTransformedValue

    # */

    # interface DataTransformerInterface

    # {

    # /**

    # * Transforms a value from the original representation to a transformed representation.

    # *

    # * This method is called when the form field is initialized with its default
    data, on

    # * two occasions for two types of transformers:

    # *

    # * 1. Model transformers which normalize the model data.

    # *    This is mainly useful when the same form type (the same configuration)

    # *    has to handle different kind of underlying data, e.g The DateType can

    # *    deal with strings or \DateTime objects as input.

    # *

    # * 2. View transformers which adapt the normalized data to the view format.

    # *    a/ When the form is simple, the value returned by convention is used

    # *       directly in the view and thus can only be a string or an array. In

    # *       this case the data class should be null.

    # *

    # *    b/ When the form is compound the returned value should be an array or

    # *       an object to be mapped to the children. Each property of the compound

    # *       data will be used as model data by each child and will be transformed

    # *       too. In this case data class should be the class of the object, or null

    # *       when it is an array.

    # *

    # * All transformers are called in a configured order from model data to view
    value.

    # * At the end of this chain the view data will be validated against the data
    class

    # * setting.

    # *

    # * This method must be able to deal with empty values. Usually this will

    # * be NULL, but depending on your implementation other empty values are

    # * possible as well (such as empty strings). The reasoning behind this is

    # * that data transformers must be chainable. If the transform() method

    # * of the first data transformer outputs NULL, the second must be able to

    # * process that value.

    # *

    # * @param TValue|null $value The value in the original representation

    # *

    # * @return TTransformedValue|null

    # *

    # * @throws TransformationFailedException when the transformation fails'
- name: reverseTransform
  visibility: public
  parameters:
  - name: value
  comment: '# * Transforms a value from the transformed representation to its original

    # * representation.

    # *

    # * This method is called when {@link Form::submit()} is called to transform the
    requests tainted data

    # * into an acceptable format.

    # *

    # * The same transformers are called in the reverse order so the responsibility
    is to

    # * return one of the types that would be expected as input of transform().

    # *

    # * This method must be able to deal with empty values. Usually this will

    # * be an empty string, but depending on your implementation other empty

    # * values are possible as well (such as NULL). The reasoning behind

    # * this is that value transformers must be chainable. If the

    # * reverseTransform() method of the first value transformer outputs an

    # * empty string, the second value transformer must be able to process that

    # * value.

    # *

    # * By convention, reverseTransform() should return NULL if an empty string

    # * is passed.

    # *

    # * @param TTransformedValue|null $value The value in the transformed representation

    # *

    # * @return TValue|null

    # *

    # * @throws TransformationFailedException when the transformation fails'
traits:
- Symfony\Component\Form\Exception\TransformationFailedException
interfaces: []