Unique Order ID

/*

 * Create a unique_id Smart Tag and assign it to each form submission.

 *

 * @link https://wpforms.com/developers/how-to-create-a-unique-id-for-each-form-entry/

 */

// Generate Unique ID Smart Tag for WPForms

function wpf_dev_register_smarttag( $tags ) {

    // Key is the tag, item is the tag name.

    $tags['unique_id'] = 'Unique ID';

    return $tags;

}

add_filter( 'wpforms_smart_tags', 'wpf_dev_register_smarttag' );

// Generate Unique ID value

function wpf_dev_process_smarttag( $content, $tag, $form_data, $fields, $entry_id ) {

    // Only run if it is our desired tag.

    if ( 'unique_id' === $tag && !$entry_id ) {

        // Replace the tag with our Unique ID that will be prefixed with wpf.

        $content = str_replace( '{unique_id}', uniqid( 'wpf', true ), $content );

    } elseif ( 'unique_id' === $tag && $entry_id ) {

        foreach ( $form_data['fields'] as $field ) {

            if ( preg_match( '/\b{unique_id}\b/', $field['default_value'] ) ) {

                $field_id = $field['id'];

                break;

            }

        }

        $content = str_replace( '{unique_id}', $fields[$field_id]['value'], $content );

    }

    return $content;

}

add_filter( 'wpforms_smart_tag_process', 'wpf_dev_process_smarttag', 10, 5 );