How to Perform Field Comparisons Within Your WPForms

/**

 * Perform Field Comparisons

 *

 * @link https://wpforms.com/developers/how-to-perform-field-comparisons-within-your-wpforms/

 */

function wpf_dev_compare_fields( $fields, $entry, $form_data ) {

    // Only run this snippet on the form ID 1000

    if ( absint( $form_data[ 'id' ] ) !== 1000 ) {

        return $fields;

    }

    // Enter the field ID for the first phone number

    $phone_1 = $fields[3][ 'value' ];

    // Enter the field ID for the second phone number

    $phone_2 = $fields[4][ 'value' ];

    // Regex pattern to match a simple 10-digit phone number

    $pattern = '/^\d{10}$/';

    // Now check if both phone numbers match the pattern

    if ( !preg_match( $pattern, $phone_1 ) || !preg_match( $pattern, $phone_2 ) || $phone_1 !== $phone_2 ) {

        wpforms()->process->errors[$form_data[ 'id' ]][ 'header' ] = esc_html__( 'Your phone number must be the same in both fields.', 'wpforms' );

    }

}

add_action( 'wpforms_process', 'wpf_dev_compare_fields', 10, 3 );