Custom WordPress Function: body_has_class

body-has-class.php

<?php
/**
 * Custom WordPress function to check if the HTML body `class` attribute
 * contains one or many specified `className` values.
 *
 * @author  Davey Jacobson <djacobson@usarugby.org>
 * @version 1.0.0
 */
if ( ! function_exists( 'body_has_class' ) ) {
    /**
     * Check if the `body` has one or many specified classes.
     *
     * @example {
     *    Checking for a single class:
     *
     *        `if ( body_has_class( 'this-html-class' ) ) { ... }`
     *
     *    Checking for multiple classes:
     *
     *        `if ( body_has_class( array( 'random-class__1', 'random-class-two' ) ) ) { ... }`
     * }
     *
     * @param  string|array $class Class or classes to check for.
     * @return bool                True if found. False if not found.
     */
    function body_has_class( $class = null ) {

        // Fail silently if `$class` is not provided.
        if ( is_null( $class ) ) {
            return false;
        }
        else {

            // Final boolean result.
            static $body_class = null;

            // Retrieve the current body `classList` as an array.
            $classes = get_body_class();

            if ( is_string( (string) $class ) ) {

                $body_class = ( in_array( $class, $classes ) ? true : false );

            }
            elseif ( is_array( (array) $class ) ) {

                /**
                 * Borrowed from `in_array_any`
                 *
                 * @author Rok Kralj
                 * @see {@link https://stackoverflow.com/a/11040612/1155068}
                 */
                 $body_class = !!array_intersect( $class, $classes );

            }

            // Final check to make sure there's a result.
            if ( ! is_null( $body_class ) ) {
                return $body_class;
            }
            // Default to `false` otherwise.
            else {
                return false;
            }
        }
    }
}