..  include:: /Includes.rst.txt
properties.elementErrorClassAttribute
-------------------------------------

:aspect:`Option path`
    prototypes.<prototypeIdentifier>.formElementsDefinition.ImageUpload.properties.elementErrorClassAttribute

:aspect:`Data type`
    string

:aspect:`Needed by`
    Frontend/ Backend (form editor)

:aspect:`Overwritable within form definition`
    Yes

:aspect:`form editor can write this property into the form definition (for prototype 'standard')`
    No

:aspect:`Mandatory`
    No

:aspect:`Default value (for prototype 'standard')`
    ..  code-block:: yaml
        :linenos:
        :emphasize-lines: 5

        ImageUpload:
          properties:
            containerClassAttribute: input
            elementClassAttribute: lightbox
            elementErrorClassAttribute: error
            saveToFileMount: '1:/user_upload/'
            allowedMimeTypes:
              - image/jpeg
              - image/png
              - image/bmp
            imageLinkMaxWidth: 500
            imageMaxWidth: 500
            imageMaxHeight: 500

..  :aspect:`Good to know`
    ToDo

:aspect:`Description`
    A CSS class which is written to the form element if validation errors exists.
