### [wpforms_process_validate_checkbox](https://wpforms.com/developers/wpforms_process_validate_checkbox/)

**Published:** October 6, 2020
**Author:** Editorial Team

**Excerpt:** The wpforms_process_validate_checkbox action fires validation on the Checkbox form field when the form is submitted. 


**Content:**

## Description

The `wpforms_process_validate_checkbox` action fires validation on the **Checkbox** form field when the form is submitted.

## Parameters

$field\_id*(int)* Field ID.$field\_submit*(array)* Original raw/unsanitized field value submitted for the field.$form\_data*(array)* Processed form settings/data, prepared to be used later.## Source

`wpforms/includes/class-process.php`

## More Information

The `wpforms_process_validate_checkbox` filter is applied to an array for **Checkbox** form field. This function can be used for all form fields `do_action( "wpforms_process_validate_{$field_type}", $field_id, $field_submit, $form_data )`.

It’s important to note that field values are not sanitized until later on in the processing, at `wpforms_process_format_{$field_type}`.the

## Examples

In this example shown below, the function will check the **Checkboxes** form field for a minimum number of choices to be selected.

```

/*
 * Check the Checkboxes field for minimum number of choices.
 *
 * @link https://wpforms.com/developers/wpforms_process_validate_checkbox/
 *
 * @param int     $field_id        Field ID.
 * @param array   $field_submit    Unsanitized field value submitted for the field.
 * @param array   $form_data       Form data and settings.
*/

function wpf_checkbox_validation( $field_id, $field_submit, $form_data ) {
 
    $field_submit  = (array) $field_submit;
 
    $count_choices = count( $field_submit );
    if ( $count_choices < 2 ) {
        wpforms()->process->errors[ $form_data[ 'id' ] ][ $field_id ] = __( 'Please select at least 2 options', 'plugin-domain' );
 
    }
 
}
add_action( 'wpforms_process_validate_checkbox', 'wpf_checkbox_validation', 10, 3 );

```

## Related

Article Reference: [How to Set a Minimum Number of Choices for a Checkbox](https://wpforms.com/developers/how-to-set-a-minimum-number-of-choices-for-a-checkbox/ "How to Set a Minimum Number of Choices for a Checkbox")

**Categories:** Actions Hooks

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